What's the relationship between local/online in a device that can be always online?You want video and audio downloaded only when wifi is around so you can enjoy them even if you are offline. Almost the same with pictures.

Microblogging is not a problem, although it would be nice to have a Save Links option when microblogs point to full pagess and/with media.

The advantage of a desktop plugin is the possibility to push the feeds and put the latest automatically in front of me. This is what Mauku does well. My device is almost never in my pocket. When I'm not doing anything with I leave it on the table and look at it when Mauku wakes up the screen.