Debian does move slowly (that's why it is good for servers; you don't have to update often) but you probably need to update your server. On Debian Wheezy, I have got Vim 7.3.547.
Edit: and no, it wouldn't be available to Debian Squeeze users, since it is served as an update to Wheezy users and not as a separate package (even if it was, it would have been made available only to Wheezy).
I believe due to a mistake it ended up on Debian 6 (Squeeze). Still, shouldn't 7.3 be available via apt-get?