Read my indepth review of TP versus TP2 in the review section. I spent a LOT of time of the need to upgrade for a corporate roadwarrior. If you are looking at this phone for just pure productivity business uses - the line is thin but there. Add in the additional capabilities of a larger screen and increased speed the TP2 easily steam rolls the TP.
I was using my TP2 in my car with a collegue and he was sorely envious. He was watching me listen to music in the background, touching the screen to get to the navigation software, taking in speaker phone calls without extra hardware or BT linking, he was hugely jealous and wanted to steal my phone shortly after watching me use it... it is indeed a MUCH better phone and worth its weight and title as the best Windows Mobile (soon to be Windows Phone) available on the market.
This is a link to my lengthy review
http://forum.ppcgeeks.com/showthread.php?t=77471&page=4
BIG Pros:
Screen, Battery Life (much better), Keyboard (much better), Speed, TF3D 2.1 (yes... just better than 2.0), 3.5mm jack, speaker and speaker phone capabilities (noise cancellation is very good), screen sensor, sensativity of the screen, Did I say SCREEN? SCREEN, SCREEN, SCREEN!
Small Cons:
Hardware buttons, bigger unit, no camera flash, no magnetic stylus
Just my issues with WM6.1
Layout still too much PPC - need more PHONE
Not finger friendly enough (close a window and even with my sizeable hands stretching becomes the forte!)