diff --git a/shell/model/Owner.py b/shell/model/Owner.py
index c49810e9..3e77d616 100644
--- a/shell/model/Owner.py
+++ b/shell/model/Owner.py
@@ -16,7 +16,7 @@ class ShellOwner(object):
 	"""Class representing the owner of this machine/instance.  This class
 	runs in the shell and serves up the buddy icon and other stuff.  It's the
 	server portion of the Owner, paired with the client portion in Buddy.py."""
-	def __init__(self, shell):
+	def __init__(self):
 		profile = conf.get_profile()
 
 		self._nick = profile.get_nick_name()
@@ -35,8 +35,6 @@ class ShellOwner(object):
 
 		self._invites = Invites()
 
-		self._shell = shell
-		self._shell.connect('activity-changed', self.__activity_changed_cb)
 		self._last_activity_update = time.time()
 		self._pending_activity_update_timer = None
 		self._pending_activity_update = None
@@ -51,10 +49,6 @@ class ShellOwner(object):
 		# Create and announce our presence
 		color = conf.get_profile().get_color()
 		props = {'color':color.to_string()}
-		activity = self._shell.get_current_activity()
-		if activity is not None:
-			props['cur_activity':activity.get_id()]
-			self._last_activity_update = time.time()
 		self._service = self._pservice.register_service(self._nick,
 				PRESENCE_SERVICE_TYPE, properties=props)
 		logging.debug("Owner '%s' using port %d" % (self._nick, self._service.get_port()))
@@ -79,10 +73,10 @@ class ShellOwner(object):
 		logging.debug("*** Updating current activity to %s" % self._pending_activity_update)
 		return False
 
-	def __activity_changed_cb(self, shell, activity):
+	def set_current_activity(self, activity_id):
 		"""Update our presence service with the latest activity, but no
 		more frequently than every 30 seconds"""
-		self._pending_activity_update = activity.get_id()
+		self._pending_activity_update = activity_id
 		# If there's no pending update, we must not have updated it in the
 		# last 30 seconds (except for the initial update, hence we also check
 		# for the last update)
diff --git a/shell/model/ShellModel.py b/shell/model/ShellModel.py
index 0820b443..5872b027 100644
--- a/shell/model/ShellModel.py
+++ b/shell/model/ShellModel.py
@@ -1,29 +1,15 @@
-import gobject
-
 from sugar.presence import PresenceService
 from model.Friends import Friends
 from model.Owner import ShellOwner
 
-class ShellModel(gobject.GObject):
-	__gsignals__ = {
-		'activity-opened':  (gobject.SIGNAL_RUN_FIRST,
-							 gobject.TYPE_NONE, ([gobject.TYPE_PYOBJECT])),
-		'activity-changed': (gobject.SIGNAL_RUN_FIRST,
-							 gobject.TYPE_NONE, ([gobject.TYPE_PYOBJECT])),
-		'activity-closed':  (gobject.SIGNAL_RUN_FIRST,
-							 gobject.TYPE_NONE, ([gobject.TYPE_PYOBJECT]))
-	}
-
+class ShellModel:
 	def __init__(self):
-		gobject.GObject.__init__(self)
-
-		self._hosts = {}
 		self._current_activity = None
 
 		PresenceService.start()
 		self._pservice = PresenceService.get_instance()
 
-		self._owner = ShellOwner(self)
+		self._owner = ShellOwner()
 		self._owner.announce()
 		self._friends = Friends()
 
@@ -36,29 +22,9 @@ class ShellModel(gobject.GObject):
 	def get_owner(self):
 		return self._owner
 
-	def add_activity(self, activity_host):
-		self._hosts[activity_host.get_xid()] = activity_host
-		self.emit('activity-opened', activity_host)
-
-	def set_current_activity(self, activity_xid):
-		activity_host = self._hosts[activity_xid]
-		if self._current_activity == activity_host:
-			return
-
-		self._current_activity = activity_host
-		self.emit('activity-changed', activity_host)
-
-	def remove_activity(self, activity_xid):
-		if self._hosts.has_key(activity_xid):
-			host = self._hosts[activity_xid]
-			self.emit('activity-closed', host)
-			del self._hosts[activity_xid]
-
-	def get_activity(self, activity_id):
-		for host in self._hosts.values():
-			if host.get_id() == activity_id:
-				return host
-		return None
+	def set_current_activity(self, activity_id):
+		self._current_activity = activity_id
+		self._owner.set_current_activity(activity_id)
 
 	def get_current_activity(self):
 		return self._current_activity
diff --git a/shell/view/Shell.py b/shell/view/Shell.py
index 74f03b4e..f56f62df 100644
--- a/shell/view/Shell.py
+++ b/shell/view/Shell.py
@@ -13,10 +13,20 @@ from globalkeys import KeyGrabber
 import sugar
 
 class Shell(gobject.GObject):
+	__gsignals__ = {
+		'activity-opened':  (gobject.SIGNAL_RUN_FIRST,
+							 gobject.TYPE_NONE, ([gobject.TYPE_PYOBJECT])),
+		'activity-changed': (gobject.SIGNAL_RUN_FIRST,
+							 gobject.TYPE_NONE, ([gobject.TYPE_PYOBJECT])),
+		'activity-closed':  (gobject.SIGNAL_RUN_FIRST,
+							 gobject.TYPE_NONE, ([gobject.TYPE_PYOBJECT]))
+	}
+
 	def __init__(self, model):
 		gobject.GObject.__init__(self)
 
 		self._model = model
+		self._hosts = {}
 		self._screen = wnck.screen_get_default()
 		self._grid = Grid()
 
@@ -57,16 +67,33 @@ class Shell(gobject.GObject):
 
 	def __window_opened_cb(self, screen, window):
 		if window.get_window_type() == wnck.WINDOW_NORMAL:
-			self._model.add_activity(ActivityHost(self, window))
+			activity_host = ActivityHost(self, window)
+			self._hosts[activity_host.get_xid()] = activity_host
+			self.emit('activity-opened', activity_host)
 
 	def __active_window_changed_cb(self, screen):
 		window = screen.get_active_window()
-		if window and window.get_window_type() == wnck.WINDOW_NORMAL:
-			self._model.set_current_activity(window.get_xid())
+
+		if window == None:
+			self._model.set_current_activity(None)
+			self.emit('activity-changed', None)
+
+		if window.get_window_type() == wnck.WINDOW_NORMAL:
+			activity_host = self._hosts[window.get_xid()]
+
+			current = self._model.get_current_activity()
+			if activity_host.get_id() == current:
+				return
+
+			self._model.set_current_activity(activity_host.get_id())
+			self.emit('activity-changed', activity_host)
 
 	def __window_closed_cb(self, screen, window):
 		if window.get_window_type() == wnck.WINDOW_NORMAL:
-			self._model.remove_activity(window.get_xid())
+			if self._hosts.has_key(window.get_xid()):
+				host = self._hosts[window.get_xid()]
+				self.emit('activity-closed', host)
+				del self._hosts[window.get_xid()]
 
 	def get_model(self):
 		return self._model
@@ -100,3 +127,16 @@ class Shell(gobject.GObject):
 		else:
 			self._screen.toggle_showing_desktop(True)
 			self._home_window.set_zoom_level(level)
+
+	def get_current_activity(self):
+		activity_id = self._model.get_current_activity()
+		if activity_id:
+			return self._get_activity(activity_id)
+		else:
+			return None
+
+	def _get_activity(self, activity_id):
+		for host in self._hosts.values():
+			if host.get_id() == activity_id:
+				return host
+		return None
diff --git a/shell/view/frame/RightPanel.py b/shell/view/frame/RightPanel.py
index d2387611..14120590 100644
--- a/shell/view/frame/RightPanel.py
+++ b/shell/view/frame/RightPanel.py
@@ -21,8 +21,7 @@ class RightPanel(CanvasBox):
 		self._pservice.connect('activity-appeared',
 							   self.__activity_appeared_cb)
 
-		shell.get_model().connect('activity-changed',
-								  self.__activity_changed_cb)
+		shell.connect('activity-changed', self.__activity_changed_cb)
 
 	def add(self, buddy):
 		icon = BuddyIcon(self._shell, BuddyInfo(buddy))
@@ -42,7 +41,7 @@ class RightPanel(CanvasBox):
 		self._buddies = {}
 
 	def __activity_appeared_cb(self, pservice, activity_ps):
-		activity = self._shell.get_model().get_current_activity()
+		activity = self._shell.get_current_activity()
 		if activity and activity_ps.get_id() == activity.get_id():
 			self._set_activity_ps(activity_ps)
 
diff --git a/shell/view/frame/TopPanel.py b/shell/view/frame/TopPanel.py
index af07ad4c..188a7d7e 100644
--- a/shell/view/frame/TopPanel.py
+++ b/shell/view/frame/TopPanel.py
@@ -37,8 +37,7 @@ class ActivityIcon(MenuIcon):
 
 	def _action_cb(self, menu, action):
 		if action == ActivityMenu.ACTION_SHARE:
-			shell_model = self._shell.get_model()
-			activity = shell_model.get_current_activity()
+			activity = shell.get_current_activity()
 			if activity != None:
 				activity.share()
 
@@ -77,9 +76,8 @@ class TopPanel(goocanvas.Group):
 
 		self._box = box
 
-		shell_model = shell.get_model()
-		shell_model.connect('activity-changed', self._activity_changed_cb)
-		self._set_current_activity(shell_model.get_current_activity())
+		shell.connect('activity-changed', self._activity_changed_cb)
+		self._set_current_activity(shell.get_current_activity())
 
 	def _set_current_activity(self, activity):
 		if self._activity_icon:
diff --git a/shell/view/home/HomeGroup.py b/shell/view/home/HomeGroup.py
index d01ba167..f01823ef 100644
--- a/shell/view/home/HomeGroup.py
+++ b/shell/view/home/HomeGroup.py
@@ -9,9 +9,8 @@ class TasksItem(DonutItem):
 
 		self._items = {}
 
-		shell_model = shell.get_model()
-		shell_model.connect('activity_opened', self.__activity_opened_cb)
-		shell_model.connect('activity_closed', self.__activity_closed_cb)
+		shell.connect('activity_opened', self.__activity_opened_cb)
+		shell.connect('activity_closed', self.__activity_closed_cb)
 
 	def __activity_opened_cb(self, model, activity):
 		self._add(activity)