@Mike
If you compare PF management at 1998 with Exc5.5 and now with 2007, can you found any huge improvements. In my mind Microsoft has not put any effort for support us - like you - to create well controlled PF environment.
Now we are forced to move data from PFs to another platform(s). Personally I see that there has been huge unused potential on PFs. Perhaps this is because companies want to develop applications on Domino and not on Exchange. Quiet few even knows that there is a "development environment" in Outlook.
About replacing PF with MOSS and File Shares, so far MOSS has not been ready yet for taking the PF roles. Shared address books, content replication between foreign offices, shared calendars.
But who knows, time is going forward, and MOSS is coming better and better. Maybe it is time to check this again..