Activity streams have established their position at the core of the social intranet. Some even consider them as the replacement of email. However, this is a dangerous interpretation to make, because activity streams are by their nature ill-suited to replace email in all the purposes it is used for. They are a very good replacement when it comes to purposes email was never particularly good for, but a full analogy is not very solid.
In this post, I will look into what activity streams are good for, and why that means that they should not be filtered.