I suspect many of the details will be posted to their web site in the next week or so, but the 18 January 2006 edition of German automobile magazine Auto Motor und Sport reveals an entirely new BMW concept which has largely escaped our attention to this point: the X Sport. 

This cover shot gives you some idea as to the basic lines of the proposed machine.  While reminiscent of the new 3er in some respects, it features a rear profile that is visually more akin to the out-of-production M Coupe.

The vehicle is being billed as a "sports coupe" despite the four-door design -- and a total length of nearly 16" -- and  is to be equipped with six- and eight-cylinder powerplants. 

An advanced All Wheel Drive system serves as something of a cornerstone for the design, and explains the rationale behind the "X" model designation.  Should the X Sport make it into production (which appears likely), expect it to appear as a 2008 model.