User status should be contextualized

We have two locations where the statuses can be published:

• User statuses sent from the user profile should be broadcasted and shown in activity streams of the personal social network
• User statuses sent from the workspace home page should be shown only on activity streams related to the workspace

In general a "context" attribute for the user status should provide information for performing contextual filtering. The context field could be multivalued (specially for things like "external, facebook" or "external, twitter").