This is being debated elsewhere, but the most current info I can find via YH a/o 12-30-11 is 821.44M.
The last contact I had with the IR firm who no longer represents us, was 422M a/o 9-30-11 and I'd say since it came from a verifiable source it's accurate.
I have found discrepancies over the years via YH, so take 821.44M FWIW.