Imagine a portable Mac reduced to the form factor of a modest tablet (the size of a Newton), with a solid-state drive, multitouch display, and wired/wireless docking capabilities to convert to a full workstation wherever you choose to park yourself. This is the suggested 'Brick' product, allowing you to "carry everything with you" without the burden of a full laptop. The MacBook Air, our source indicates, was in some respects a technology greenhouse for the engineering chops needed to build the next-gen portable.
Along with this product concept, the other item our source noted was that the full Mac portable line should be getting multitouch displays at some near date, enabling some spectacular new interface concepts while not replacing the trackpad and keyboard.
Is this a plausible product -- or, more to the point, a saleable one? If Apple can leverage some technologies that have been just around the corner for a (long) while now: wireless charging, USB and FireWire sans cords, wireless video, and low-power CPUs ... a device that could bring the on-the-go interface and capabilities of the iPhone/iPod touch family while serving as a desktop replacement when you get back to base would be pretty darned awesome.
Thanks Mr. X