The original Touch Diamond quickly became one of HTC’s best selling devices of all time. In fact, Microsoft recognizes it as one of the best selling Windows Mobile phones of all time.

Building on this success, HTC has announced the Touch Diamond 2 at MWC (press release). Before we get into the cool new stuff, let’s stalk specs. HTC is going with the maximum resolution allowed by Windows Mobile: 800×480, in a petite 3.2″ screen. That makes for an insane screen pixel density of 292ppi, meaning objects on the screen will be super duper crisp. It’s running on a Qualcomm MSM7200A CPU clock at 528MHz, 512MB ROM, 288MB RAM, aGPS, WiFi, FM Radio, an accelerometer, a 5MP camera on the rear (no flash), and a 1100 mAh battery. It looks like Q2 is being targeted for a Europe/Asia release, and summertime for the states. HTC is saying that the Touch Diamond 2 is running on WinMo 6.1, but we can’t help but think that it’ll ship with 6.5.

So how is the Touch Diamond 2 different than the original?

1. Size: the new Touch Diamond is about 2mm thicker than the old. We think some added thickness is a fair trade for a larger and higher resolution screen.

2. Screen: the old Touch Diamond ran at VGA (640×480) resolution at 2.8 inches, while the new Touch Diamond is kicking WVGA (800×480) resolution at 3.2 inches.

3. Zoom slider: like the Touch Pro 2, the new Diamond has a capacitive zoom slider which will come in handy for moving in closer anywhere that a zoom is required (web, Google Maps, photos, etc).

4. Diamond faceting: is gone! It seems that the diamond faceting on the rear of the original Touch Diamond wasn’t popular enough to bring it over to the new version.

5. No D-Pad: also like the new Touch Pro 2, the Diamond 2 lacks a D-Pad, which we aren’t too happy about considering how much one-handed usability can be had with a D-Pad in Windows Mobile.

6. Battery life: HTC is claiming a 50% boost in juice. Wow, that’s pretty substantial, and we hope it’s true

7. Revamped TouchFLO 3D: more on this later, but it looks like each contact will have their own TouchFLO 3D interface, letting you “find all email from Jane” or “see all texts from Jane,” etc. This could be a really awesome concept.

You’ll be hearing a lot more about the new Diamond 2 in the coming weeks, but from what we see here, HTC has brought a proper level of innovation to the successor of a very popular device. Check out HTC for more.

Update: Here is some video love from EngadgetMobile. A few takeaways: first, like the Touch Pro 2, hitting the Start button on the device or screen will open the TouchFLO 3D program launcher, which we think is a temporary cover up until WinMo 6.5 gets out the gate. Second, the larger size of the Diamond 2 really stands out…it no longer has the smallish appearance of the Diamond (see size comparisons).