Here's a more detailed description of the concept from the document filed by RIM:
Wireless handheld mobile communication device including a housing with a display above a keyboard exposed for user actuation. A length of the device is greater than the width. Each key of a right-hand keyfield has a longitudinal axis oriented at a left-to-right inclined angle while each key of a left-hand keyfield has a longitudinal axis oriented at a right-to-left inclined angle from the vertical centerline. A left boundary of the keyboard is located adjacent the left lateral side edge of the device and the right boundary of the keyboard is located adjacent the right lateral side edge of the device so that the keyboard spans a substantial entirety of the width of the device.
To a see a sketch of the proposed angular keyboard, click here.
The new keyboard design is meant to improve text entry on mobile devices. The patent application filed by RIM doesn't mention BlackBerrys specifically, but it appears that the keyboard is meant to be implemented on future BlackBerry models.
Hopefully this will help eliminate a vast number of typing errors and solve the "sore thumb" problem suffered by many BlackBerry users. How long do we have to wait for an actual product? That remains a mystery since the keyboard is just a concept.
Also, it's not an entirely new concept. Perhaps RIM has something different and more elaborate in mind than the sketch of the keyboard indicates, but there are smartphones already available with slanted/slightly angular keyboards. One example is Motorola's Moto Q.
If you've spotted other smartphones with a similar design, let us know.