Its name, or codename, is Colt. BlackBerry Colt. This will apparently be the high-end flagship that RIM has needed for a long while. Here's a render of what the Colt might look like:
The phone that ends up being released may not be identical to what you see in the image above, but it will be close. As for specs, we have a whole bunch of them neatly leaked for your convenience.
A single-core 1.2 GHz processor (as seen in the Bold 9900) was used in the first testing phase, but a dual-core CPU is currently inside prototypes, so that may be the chip the Colt ends up shipping with. There will also be a touchscreen (at least 4-inch) with a resolution higher than 900 pixels and two cameras, one at the front and one at the back. The Colt will be thinner than the Bold 9900 and 9930, but will have a similar unibody outer stainless steel frame, no physical buttons, a similar battery to that found in the PlayBook, and new transitions which should make the UI feel fluid.