I'm another one in this camp - I'm happy with my Treo and the smooth sync of NUTD/C. I'd really like to move to the iPhone, but can't have it be a pain to keep sync'd with my home and office calendars, which are all on NUTD.

I've purchased a 10-license upgrade to NightHawk, and one of my driving concepts was that it would help support the iPhone transition, but since it now looks like NH is going to be several months later than the iPhone, I need to either wait on the iPhone, or have a solid sync strategy for the current software.

Just so ya know, it's not just Now - I'm also fretful about whether the iPhone will support IMAP IDLE like Chattermail for Treo does, giving me true push from my own IMAP server - I'm loathe to give that up also.

If I can't get iPhone to do push from my server, or sync with my calendar/contacts, that might be a deal killer.