I work at a small bank in MS, and we are near completion of migrating our 600+ users from Lotus Domino to Ex2k7. The first phase was to migrate all users to Exchange, and have them use OWA until we can provide Office 2007 to all users (phase 2). Two main complaints of my users have been the missing ability to create personal distribution lists and the ability to "send & file" their sent emails (instead of dumping all sent emails into the sent items folder).
I am glad to see the personal distribution lists issue will be addressed in SP1, and would like to see a "send & file" option added in future releases. I have found an Outlook add-in (QuickFile) that may be a temporary solution for some of my Outlook users, but it would be nice if this was native to OWA and Outlook 2007.