First thought: It's disgusting that the White House is trying to relegate its statements about Iraq to the Memory Hole.
Second thought: It's great to live in a free country where this doesn't work.
Third thought: This demonstrates the same level of technical (in)competence we see in so many things this Administration does.
Fourth thought: Maybe it does work more often than not — many people have come to rely on Google. Efforts like this often won't get spotted most of the time.
Fifith set of thoughts: How do we prevent, or at least identify and publicize and warn about, this sort of activity in the future? Will this mean that commercial databases which keep pristine copies of things and promise not to santize still have a place? Can something like archive.org overcome this sort of attack on our online history? Is there anything Congress could or should do about this? (Needen't ask “would”—we know the answer to that.)
Update: Sixth thought: Well, they just made it much less accessible (although people who rely on google might get the idea the statements didn't exist), as far as we know they didn't actually delete them. It could be worse. But it's also more deniable.
Seventh thought: If I ran Google, would I now instruct my spiders to ignore the robots.txt file at whitehouse.gov?