E2K7 - RUS RIP

Yes, when you get moved over to Exchange 2007, the Recipient Update Service (RUS) will be no more. When it worked, we really did not think much about it (except for that delay between creating a new mail-enabled object and the time when it got its e-mail addresses). When it did not work, though, heaven help you! I have heard stories of organizations that wrote their own provisioning tools specifically to get around the shortcomings of the RUS.

Evan Dodds wrote a great Exchange Team blog entry called Good bye RUS. Go forth and read it! And, it includes some good information that you will need to know during a period of interoperability E2K/E2K3 and E2K7)