@Lindy I like streams a lot especially the ability to stream all content in one list instead of just forums etc. My Blogs are pretty much dead but when I upgrade to 4 finally I am going to jump start them, and then members will realize that the discovery is much better and hopefully they will start using them instead of making "bloggy" type forum posts. Same for status updates, and all content. The method of discovery is much better when I felt like in 3.4 it was hidden (except for forums, which made everyone only want to use forums). This, overall, makes for better social engagement.
What I think can be improved is filtering the stream you are in instead of creating a new stream. We can set defaults and rely on member creation, and yes, there is edit/update, but 3.4 had the pane on the left where you could filter on the fly. If you can't do live filters, maybe there is some middlegound here. Like, a menu could actually contain member or site defaults (saved by member). Say, top 5. So instead of having the filtering abilty on the left, you have your top 5 presets (streams) readily clickable in the stream. I'm not sure where this would fit layout-wise, perhaps horizontal is best so at the top. But it would save clicks from going to the menu, and also, for perception's sake, creates "filters." Most members will have a few streams they bounce between, and having those right there would be great.
Otherwise, streams are are great tool and I am looking forward to getting my members to actually use other apps!
And as @tekguru mentioned, yes, the first bug he posted needs attention, as well as this bug, and the first unread setting which I believe is coming soon.
Wish list:
I would like to reorder streams in menu.
I would like to set AA as site default (can't, not sure if bug).
I would like to be able to add the "Likes" etc. to another stream to clone AA but customize.
Thanks!