Offline messages can be good and bad.
I'd personally like a combined MSN Windows Messenger so you don't need both to do everything, but I don't think that will happen with this next version.
I'd also like a way to comment and/or override people's displayed user names. I hate how people can change them at anytime, so it takes some work to keep track of whose really who. I know the e-mail addresses are there, but I'd like to be able to make my own comment.