Sony Alpha a99 review | Digital slrs/hybrids Reviews | TechRadar:

"After a four-year wait, Sony has brought out a replacement to the full-frame Alpha a900 camera, the 24.3MP Sony Alpha a99.
Unlike the Sony a900, which was a DSLR, the Sony a99 is a DSLT, or Digital Single Lens Translucent camera. This means that instead of having a mirror that flips up to enable the exposure to take place, the Sony Alpha a99 has a fixed translucent (or transmissive) mirror that allows 70% of the light reaching it to pass through and onto the imaging sensor."