I’ve seen several queries in various fora about using Entourage with Exchange 2007. I’ve been using it for a while and have had absolutely no problems. There are a couple of issues to be aware of, though.
First, if your mailbox is on Exchange 2007, and you’re accessing it through an Exchange 2003 front-end, Entourage should work OK, but you won’t get any of the Exchange 2007-specific features when you use OWA. I haven’t tested hitting an Exchange 2003 mailbox from an Exchange 2007 CAS (client access server); maybe Devin could give it a try.
Second, don’t put “/exchange” in the Exchange server field of the account properties dialog. That’s because an Exchange 2007 CAS serves OWA from the /owa virtual directory. If you just put the mail server name in (see below), Entourage will Do the Right Thing (thanks to some detective work by Andy Ruff).