I have attached a patch that avoids the bug, changing usage.py in novaclient.  I'm not sure if this is the right fix, but after this change I can log into the console.  If I then click on any of the tabs, I get errors.  Example:

[Wed Mar 28 22:03:12 2012] [error] CRITICAL:openstack_dashboard:Unhandled Exception in of type "<type 'exceptions.KeyError'>" in dashboard.
[Wed Mar 28 22:03:12 2012] [error] Traceback (most recent call last):
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/pymodules/python2.7/django/core/handlers/base.py", line 111, in get_response
[Wed Mar 28 22:03:12 2012] [error]     response = callback(request, *callback_args, **callback_kwargs)
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/python2.7/dist-packages/horizon/decorators.py", line 40, in dec
[Wed Mar 28 22:03:12 2012] [error]     return view_func(request, *args, **kwargs)
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/python2.7/dist-packages/horizon/decorators.py", line 55, in dec
[Wed Mar 28 22:03:12 2012] [error]     return view_func(request, *args, **kwargs)
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/python2.7/dist-packages/horizon/decorators.py", line 40, in dec
[Wed Mar 28 22:03:12 2012] [error]     return view_func(request, *args, **kwargs)
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/pymodules/python2.7/django/views/generic/base.py", line 47, in view
[Wed Mar 28 22:03:12 2012] [error]     return self.dispatch(request, *args, **kwargs)
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/pymodules/python2.7/django/views/generic/base.py", line 68, in dispatch
[Wed Mar 28 22:03:12 2012] [error]     return handler(request, *args, **kwargs)
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/python2.7/dist-packages/horizon/tables/views.py", line 105, in get
[Wed Mar 28 22:03:12 2012] [error]     handled = self.construct_tables()
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/python2.7/dist-packages/horizon/tables/views.py", line 96, in construct_tables
[Wed Mar 28 22:03:12 2012] [error]     handled = self.handle_table(table)
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/python2.7/dist-packages/horizon/tables/views.py", line 68, in handle_table
[Wed Mar 28 22:03:12 2012] [error]     data = self._get_data_dict()
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/python2.7/dist-packages/horizon/tables/views.py", line 37, in _get_data_dict
[Wed Mar 28 22:03:12 2012] [error]     self._data[table._meta.name] = data_func()
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/python2.7/dist-packages/horizon/dashboards/nova/instances_and_volumes/views.py", line 52, in get_instances_data
[Wed Mar 28 22:03:12 2012] [error]     exceptions.handle(self.request, _('Unable to retrieve instances.'))
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/python2.7/dist-packages/horizon/dashboards/nova/instances_and_volumes/views.py", line 49, in get_instances_data
[Wed Mar 28 22:03:12 2012] [error]     instances = api.server_list(self.request)
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/python2.7/dist-packages/horizon/api/nova.py", line 309, in server_list
[Wed Mar 28 22:03:12 2012] [error]     servers.list(True, search_opts)]
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/python2.7/dist-packages/novaclient/v1_1/servers.py", line 279, in list
[Wed Mar 28 22:03:12 2012] [error]     return self._list("/servers%s%s" % (detail, query_string), "servers")
[Wed Mar 28 22:03:12 2012] [error]   File "/usr/lib/python2.7/dist-packages/novaclient/base.py", line 76, in _list
[Wed Mar 28 22:03:12 2012] [error]     data = body[response_key]
[Wed Mar 28 22:03:12 2012] [error] KeyError: 'servers'