Ryan just sent me the URL and username/password to download the 0.4.8 version of flock.
First impressions is that the app is good looking. Online bookmarks via del.icio.us seems a great idea (and del.icio.us’s one at that), after thinking about RSS reading as an offline activity, bookmark/favourites are a good idea for online storage, because you only use them when your online (spelling out the obvious I know, but I’ve only just got it). I also really like the idea using tags to order/sort the bookmarks.
The blogging features are not so important to me, as I’m not always connected, so the web interfaces of msn Spaces and/or Blogger work for me presently. Especially the draft functionality.
So at this point the value add of Flock is actually the integration with del.icio.us.