I had left the bitcoinwatch screen unrefreshed and at the same time have the ClarkMoody Realtime book open:
http://bitcoin.clarkmoody.com/When I saw the realtime order book go backwards, I then went back to the bitcoinwatch page and it validated the prior value......
So, you're right, 2 different time periods, the 1st capture was the bitcoin watch quote, and the second set is the realtime book, which was the older of the 2.
DKN