One thing I've always hated about Hotmail is the fact that, after sending email, the app sends you to a page to add the people you've just sent an email to to your contact list. I guess I could stand this if I used it, but the fact is I don't; at least not often. My main annoyance is that you're sent to this page even if everyone you just sent an email to is already a contact. The page is just a waste of time that forces users to make an extra click. At least skip it in this scenario. This minor change would definitely lessen the annoyance. If you really want to improve the experience, show me that info on the follow-on page in a small module, which would give me the same capability. Alternatively, Gmail automatically added these people as contacts in one of the early versions of the system. I think that'd be a good option, but wouldn't force it across the board.
I mentioned this internally, but didn't really get much out of it. I'm not sure what the thoughts are for the future. Others did, however, agree the page was wasteful.