I guess Newegg has the latest rev with the updated PCB - maybe buy.com has the same now, but just hasn't bothered to change their listing (or hasn't noticed). It doesn't really matter either way as the drive will really perform the same unless WD worked on the mechanicals as well. Have to compare the spec sheets. Look under Mfr's Info on the newegg page > go to the product page > note in the left sidebar that both versions are listed > print out the spec sheets > compare side-by-side.
.bh.