Palm accidentally uploaded a presentation of the Palm Treo 850 to one of its public Web sites. Before they could remedy the small error, the presentation was already posted all over the blogosphere. One thing’s for sure: Palm’s new handset, which is part of the producer’s 2009 line-up, is “the best looking Palm ever.”

The Treo Pro will operate with Windows Mobile. The company’s Nova operating system is still at the stage of “long-awaited.” As the flash presentation of the Treo Pro showed on Palm’s Web site, the new handset has a much slimmer body than its forerunners and operated with Windows Mobile 6.1 over 3G. The handset, which was initially called the Treo 850, is similar to Palm’s Centro to some extent.

Treo Pro comes with a glossy black and white color scheme. The handset also comes with some improvements such as a 3.5mm headphone jack, wireless button on the side and a microUSB connector.

Treo Pro features a 2.4-inch 320 by 320 pixels touch screen display and is powered by 400MHz with 100MB of RAM. On its back it has a 2-megapixel camera and its memory expansion relies on a MicroSD card. The only thing which can’t be a + for the Treo Pro is that it is still pretty thick. Competing producers such as Motorola, Samsung, Apple and others managed to come up with thinner smartphones.

Unfortunately, Palm didn’t leak the release date too. It is unknown when it will be released, but it will surely be with a carrier such as T-Mobile or AT&T, because its first version will feature GSM/UMTS radios.