I would be interested in ISO sensitivity, focusing performance and overall speed but is that price point correct? $400 is pretty darn cheap for a 20MP APS-C sensor SLR type body camera. I have a Canon 5D MKII but this would be handy to carry about if it was that cheap.
This actually peaked my interest, If Sony can pull it off, it will drive competition probably mainly towards Nikon and Canon. I'd love a 20MP DSLR with 1080p capability for only $400.