I've been primarily using Windows Mobile Smartphones for the last year or so, with the T-Mobile Dash as my favorite device. I like the integrated QWERTY keyboard, but every once in a while I do miss a phone keypad. I thought the HTC Vox would be the device to knock out the T-Mobile Dash, but I find the Dash just too pocketable to give up even though the Vox is an excellent device. The Helio Ocean is a unique device with a dual sliding design and I personally never gave it much thought because it doesn't run Windows Mobile or S60. It appears that there may soon be a new device I'll have to look at from AT&T though as the Pantech C810 device is now up on Amazon.
There are still lots of unknown details since there has not been an official announcement, but we do know it will run Windows Mobile 6 Standard and has a 3G radio. We can also see that Amazon has it listed for a price of only US$179.99. The Pantech C810 has 7 buttons and a directional pad on the front and then slides up to reveal a phone keypad. It can also be slid sideways to reveal a full QWERTY keyboard. Thanks to Smartphone Thoughts for the heads-up on this information.