Leckness starts off with an observation that many fail to make:
Unfortunately, there is no true answer to this question. All the apps have their advantages and disadvantage. I have purchased and poked around in most of the major Twitter clients available for Windows Phone 7. I am not totally sold on which one I like the most yet, but I do have it narrowed down to a couple.
That bit of "hey, this is only my view" aside, it's on with his notes and thoughts on Rowi, Birdsong, Mendoh, Beezz, Seesmic, MoTweets, and the official client.
Read on at Gotta Be Mobile.