Update below.

We’ve known about the HTC Mondrian for months after the ROM was leaked on XDA-Developers. It’s going to be one of the first Windows Phone 7 devices from HTC. From these new leaked pictures, it appears that the device will have a slate form factor with a very predomenant Windows Flag key on the front (required for all WP7 devices).

Update: We just received some new information from the source of this leak who has actually gotten a chance to use the Mozart. Here are some new details:

1. The battery is 1400mAh with charging on the side, not the bottom (perhaps a new trend for future HTC devices)

2. There’s no microSD card slot (one of Microsoft’s requirements for Windows Phone 7)

3. The Mozart has a normal SIM module, so it’s a GSM device

4. It has a unibody design like the HTC Legend

5. Software is stock with no HTC improvements. Device feels fast and very responsive and exhibits great battery life.

The back has a large camera lens with a flash, and the casing seems to be a combination of soft-touch plastic and metallic dark silver plastic.

The back cover can actually be removed in multiple parts, which is very interesting. Like the HTC Legend, the battery slides out from the bottom. We’re curious as to why the area surrounding the camera lens can be removed.

Yup, it’s a Windows Phone 7 device for sure. Not seen here are any customizations made to the Start screen, which means that it’s definitely a prototype/early device.

(via: @Xmoo)