Hands-on Preview (Summary): "... Inside its compact body, the Canon EOS M retains much DNA from the Rebel T4i digital SLR. Shared features include an 18 megapixel APS-C CMOS image sensor with on-chip phase detection capability, a single DIGIC 5 image processor, a hybrid autofocus system that uses phase-detect to achieve approximate focus for centrally-located subjects, then fine-tunes (or performs the whole AF operation, for subjects outside the center of the frame) using contrast detection.
Like some early mirrorless models from competitors, the Canon EOS M lacks an onboard flash strobe, and offers no electronic viewfinder functionality, either built-in or as an accessory. It does, however, offer a quite capable movie mode. Resolutions up to Full HD are supported, and options include manual exposure control, internal / external stereo mics, and manual audio levels control. ..."