The official Twitter App just went to 4.0 with some facelift and speed enhancements. The update specifically targets the iPhone (iPod touch) with no mention of when the iPad will get these changes. In any case the update provides some speed tweaks and new tabs. Now you have a Connect Tab that more closely matches the experience on where you have an Interactions tab and Mentions tab. The Discover tab lets you search as well as it shows you trending stories, suggestions on who to follow and the ability to Find Friends and Browse categories. Lastly the Me tab shows your stats, Direct Messages, Drafts, Lists, Saved Searches and the ability to switch between accounts. A single tap also lets you  view your profile. This seems like a nice update and we'll have to wait and see how they implement these changes on iPad.

You can get the Twitter App for Free here from the iTunes