A handful of slides supposedly leaked from AT&T surfaced over the weekend, showing just about every smartphone coming to the carrier for the rest of the year. These include devices running Windows Mobile, BlackBerry, Palm WebOS, and Android operating systems; so you may find them particularly valuable in helping you plan out possible future purchases.

First up is the HTC Fortress, AT&T's version of the HTC Touch Pro2, which is expected to run on Windows Mobile 6.1 (presumably upgradeable to 6.5 down the road) and will feature a slide-out QWERTY keyboard as well as a large touch screen display. A branded variant of the HTC Touch Diamond2, described as Warhawk, will follow in September boasting a similar touch screen display but no hardware keyboard. HTC also plans a new Android handset, dubbed Lancaster, which is aimed at social networking and features a sideways-sliding keyboard.

It seems the HTC Lancaster was originally planned for an August launch, though that could be delayed in order to put AT&T's user interface on the device, rather than Google's. Additionally the slides mention Palm's Eos, a successor to the Centro that is expected to run WebOS, as well as an iPAQ smartphone from HP and a few BlackBerry devices that include a new Pearl supporting 3G and the upcoming Onyx.