Support for the following mirrorless cameras was added to Lightroom 4.3 and Adobe Camera Raw 7.3: Leica M-E, Nikon V2, Olympus E-PM2 and E-PL5, and Pentax Q.
As far as I can tell, this brings Adobe's raw support up to speed for all the shipping mirrorless cameras (full list of supported cameras). Only the not-yet-shipping Leica M is unsupported at this time. Fujifilm X-Pro1 and X-E1 support is still sub-optimal as far as I can tell, though.