Signal to Noise on Twitter is a good summary from Adam Curry of what Twitter feels like when added to an RSS-based stream of information consumption. It just doesn’t fit.
I find that I use Twitter and Facebook mostly on my mobile while in between other things, rather than as a source of information I visit regularly.
Additional grump: I hate not seeing threaded messages or conversations in my Twitter client. It sucks. And yes, I’m sure I can fix it by using another client.