In terms of design, performance and non-OS features, this is the best hardware Palm has ever made. The feature that deserves the most mention is the redesign—because it's beautiful. Not only is the phone comparable in size and weight to the iPhone 3G (just a bit wider and thicker), but it's visually appealing.
The shiny black case, and jewel-style Centro keyboard gives it a look that is appealing and eye-catching without being gaudy. Rounded edges prevent it from feeling too sterile, and the flush screen marks the first time a Palm touchscreen hasn't been sunken in. The 320x320 resolution screen, GPS and one-button wi-fi are all present, and the 400 MHz processor and 256 MB RAM really run Windows Mobile 6.1 well.
As far as real-life performance goes, the full-sized keyboard is definitely more useful than the one on the Centro, but the lack of definition between keys caused me to make typos on a semi-regular basis. Anywhere signal strength was strong, the 3G was speedy, and call quality was loud and clear. The GPS, complete with turn-by-turn navigation, worked well enough, but seemed to take an abnormally long time to connect to the satellite. And the touchscreen was as responsive and pinpoint accurate as Palm has ever made.
Some of the custom Palm features from the 800w, such as their own chat-style SMS interface and the GPS search bar on the home screen are absent, which is unfortunate, because they were both useful. And in direct light, the screen had a tendency to washout and be difficult to read, even on the highest brightness setting. A dedicated button to take you back to the home screen would have also been nice, but it doesn't kill the phone.
If you're looking for a Windows Mobile phone, I'd strongly consider the Treo Pro, as it has a good balance of design, features and performance for the user. And even if you're not looking for a WinMo phone, it just might tickle your fancy enough to have one around.