Quick update!

I was browsing the internet, when I came across this picture!  Look at the top of the stairs, to the right!

It's clearly a zombie/zombie shadow! Wow, I never noticed that!

I know they said the original 4 zombie maps will be included in the Hardened and Prestige Editions of the game. I don't want to over think this too much and speculate that there will be new zombie maps, but I highly doubt that they will make new zombie maps.  All in all, this was a cool picture!

*Edit: I know this picture is small but I tried uploading it to it's original size, but it was cut in many places because of the page layout. Here's the url to view the full sized image, which is much bigger.

http://xbox360.ign.com/dor/objects/14349501/call-of-duty-black-ops/images/call-of-duty-black-ops-20100702102734090.html?page=mediaFull