Over at Phone different, Mike Overbo just posted his full review of the iPhone. There are a lot of little surprising bits in there, so it's definitely worth the read. Since I'm slowly becoming the "iPhone troll in residence" amongst our little family of sites, I'm going to post the relevant 'graf for WM users (For featurephone users, it's a 9/10, btw):

It will take some big software updates to compete effectively against Blackberries and Windows Mobile and the like in the business segment. Heavy email users will want to utilize their business webmail interface (in Exchange, it's Outlook Web Access) and the VPN option for security. **On the business side, the iPhone is currently 7/10**; a "C" if you want arbitrary letter grades.

Read: Phone different: Review: Apple iPhone 8GB

I'd say I agree with that, actually. Maybe a 6/10 for me on the productivity side, but where Mike dings the iPhone for certain problems I sideswipe it. It's not that the problems can't ultimately be fixed via updates (they could) or that they're that monumental (I'm undecided), it's just that they exist in exactly the places where I need a smartphone to be powerful - Mail, ToDo, and yes, 3rd party apps.

I've been using the iPhone for a week and after a week's worth of use I was impressed, but ultimately it's not for me. I'm back to using the HTC Touch as my main brain right now. I'll explain more later this week in Part 2 of my iPhone vs. HTC Touch articles. In the meantime, check out Mike's review (and no, I'm not just linking it because it's my name on the test email and text pics).