I believe they are overvalued too.
At 4.75 a share, the market capital would be BTC1.900.000 , considering there are about 11 million bitcoins this would have ASICMINER be worth 17% of all bitcoins.
The same argument again and again. See here for the last time it was explained why it is flawed:
https://bitcointalk.org/index.php?topic=99497.msg2625069#msg2625069