I use a Windows Mobile-based phone as well. One of the things that iPhone doesn't have as of yet is support for enterprise applications. It doesn't run ActiveX, so you can't work with something like Outlook Web Access (unless you ask your IT department to change quite a few things on their end, which I hope they'll refuse to do, for their sake :)) and many other sites which use ActiveX. It just wasn't designed for the enterprise, but it looks like they're changing it with v.2 of the software. Still, I'd be quite concerned about a touchscreen-only device, didn't have much good experience with those. My phone has all the proper buttons, all 39 of them, and a touchscreen :)
The usuals, whatever I post is my opinion, yaddayaddayadda. I'm still learning this, so if you listen to me, well, good luck to you :)
