I'll start with the features that are common to both smartphones:
- They both will eventually run Windows Mobile 6.5 (the Imagio comes with 6.5 now while the Touch Pro2 comes with 6.1 but you'll get an upgrade to 6.5).
- They both have a nice large 3.6" screen at 480x800 pixels.
- They are both fast and have a nice amount of RAM.
- The both come with a 1500 mAh battery.
- You can tether using either device (Mobile Broadband Connect)
- They both have a micro SD card slot.
- They are both world phones with CDMA and GSM capabilities.
- They both have internal GPS so they can be used as a GPS navigator.
- They are both made by HTC, so you're getting a high-quality phone.
HTC Touch Pro2
- + You'll get a nice slide-out QWERTY keyboard.
- - You'll end up with a thicker device
- - no V Cast TV
- + Thinner and narrower (not by much)
- - No hardware QWERTY keyboard
- + V Cast TV (great for those slow nights when you're on call)
- + better camera (5 MP vs. 3.2 MP on the Touch Pro2)
However, if you want something that closely resembles an Apple iPhone, go with the thin and sleek HTC Imagio. I don't think you'll be disappointed because the on-screen keyboard is very easy to use and it comes with large on-screen buttons.