Tuttobiciweb are reporting that Davide Rebellin tested positive for CERA on a (very late) test. The Olympic bods are apparently reporting six new positives, including an Italian cyclist. No mention on how Tuttobici identified this as Rebellin, but they are pretty clear that it is him.
Apparently 948 tests were carried out using some new and very expensive test. Those tested were the "champions", presumably medallists. I guess that Tuttobici has more info because Tatiana Guderzo also won a medal in the Women's Road Race. Unless they just forgot her as a possibility.
Update: On Wednesday, the German Cycling Federation (BDR) confirmed that the second cyclist to test postive at the Beijing games was Stefan Schumacher.