It won't officially be released until February 19, but the AT&T version of the Samsung Galaxy Note has already had a rooted kernel built for it. The kernel also has init.d support so custom scripts can be run during the boot cycle, and is set-up for root access over adb as well. If that reads like Greek to you, just know that it's all good stuff and needed for custom ROMs and other hacks for the Note, and enjoy it.
Of course you'll need to use Odin to flash it, so that means Windows only and the mess of drivers to install. Luckily, all that is covered and put together with download links and instructions at XDA. Be sure you read them before you start clicking buttons. When you get your paws on an AT&T Note of your very own, give it a look. In the meantime, discuss it all in the forums. Happy hacking!