Found this little leak on the unannounced a750. Nothing can really be confirmed.
http://www.engadget.com/2009/10/30/sony ... f-release/
"Minolta's Sony's DSLR range was refreshed only this August, but here we are, hearing rumblings of another new addition to the bunch. Set to occupy the space between the 14.2 megapixel A550 and 24.6 megapixel full frame A850, the imaginatively titled A750 is expected to strike the perfect balance between the two with a 14.6 megapixel full frame sensor. We see what you did there, Sony, very clever. If you ask us, anything over a solid dozen million pixels is overkill and just asking for noise trouble and processing lag, so in fact chopping a third off the A850's pixels could turn out to be quite a boon for overall image quality. Then again, we've no idea what else Sony might sever from its higher offering, though we're likely to find out by CES 2010 at the latest."