I seem to be in the minority, but I don’t like the new Twitter for iPad. It looks much too cluttered, with all of those gratuitous popups & sliders. I still haven’t figured out how to get rid of the panel that appears when you tap on a tweet, other than switching to mentions, direct messages, or timeline in the far left. Entering a new tweet is even worse, with the new tweet sheet popping up above the timeline & detail panels.
I still prefer Echofon, which isn’t as pretty but is a lot more functional & usable. Echofon is still the only Twitter client that supports push notification and can sync unread between the Mac, iPhone, and iPod (which for me is the killer feature).