Just picked up my Pre yesterday. The only thing I miss from my crappy Moto Q running WM 5 is that I can't click on a phone number in email anymore (unless I just haven't figured it out yet).
The only thing I miss from my Windows Mobile phones is their longevity: I used them so seldom that they were bound to last longer than my well-used Pre.
1. notification light, i hate opening my pre every time i come back from something as small as walking downstairs and going back up
2. Calender acting as an alarm. I put business meetings in my old phone and it would go off for about 20 seconds and until i checked it, and would repeat. Setting your alarm every time sucks and you have to wait until that day to set it.
Been seeing tethering mentioned a lot. You do realize there's a tethering app for the Pre? Pretty simple to use. You may as well learn how if you're hesitant because its the only way you'll get it. Sprint/Palm won't be coming out with it and won't be approving any such apps.