Our full review of IM+ for iPad is in the works and should be appearing shortly, so I'll just hit some highlights here: With the exception of Skype chat, IM+ Lite supports the same features as the full version of IM+: Twitter, Facebook, Google Talk, Yahoo, MSN/Live Messenger, AIM/iChat, ICQ, MySpace and Jabber.
IM+ has a speech recognition option (as US$0.99 in-app purchase) and allows you to browse the Internet with a built-in browser so you needn't exit the app to follow links.
IM+ will notify you via push notifications of new email in Hotmail, Yahoo, or GMail accounts, as well as sending push notifications of new IMs on all supported networks.
The ad-free version of IM+ is $9.99, but if you haven't tried it yet, the lite version is a good way to do just that.
Unfortunately IM+ still does not support group chats in AIM (although they do work in MSN, and in Skype if you have the paid version). If you rely on that feature you'll still need to stick with BeeJiveIM.