Microsoft will be demonstrating a spherical version of their multitouch-capable Surface system at the company's Research Faculty Summit 2008 DemoFest, according to their own booth map. The phrasing suggests that Surface, which is currently a flat table that can respond to multiple points of contact (see our two hands-on demos here and here), has developed into a round display that would be more usable by a larger number of people.
A spherical touchscreen would present a variety of technical challenges no matter the mechanics. Currently, Surface use a camera to identify points of contact on the glass table-top, changing the image projected from underneath accordingly. Translating this onto a sphere would likely require multiple cameras and multiple projectors to ensure full coverage. Resistive or capacitative touchscreens are yet to be used in such large-scale or oddly shaped applications.
It's unclear whether the "Multi-Touch Spherical Display" is merely a proof-of-concept or a potential product idea. Currently Surface has found applications in AT&T stores and casinos; a version that could be used from all angles might be useful as an information point in shopping malls and resorts.