From Mr. Scoble:
It's official: get Windows XP Service Pack 2 by visiting microsoft.com/protect and making sure your automatic updates are turned on. That's the official way to get it over the Internet. Straight from Frank Shaw, Vice President at Waggener Edstrom which is Microsoft's PR agency (I asked him tonight when I saw him pop up on my IM).
Yes, MSDN Universal Subscribers also can get it right now and not wait until the system gets around to putting it on their machines.
I don't have a MSDN subscription but I thought I would check it out. Turns out there is a link on the second page Robert mentions that will take you to the MS Download site specifically found here. This version is the full version geared towards IT Professionals (wow I qualify). Basically this is the huge version that you can download, burn to a CD and go around to machines without internet access and update the machine accordingly.
The funny part of the method of getting SP2 is automatic updates. Automatic updates only works when you are an Administrator. I, along with almost everyone in my company, operate normally under a restricted user account. Automatic updates to my knowledge doesn't naturally work this way though there may be quite possibly a “hack” to get it working accordingly. Personally I still wouldn't use it because I need to test all updates and upgrades before mass deployment. I can't have something breaking because I chose to have automatic updates just fix whatever it felt like.
Update: You can configure Automatic Updates and have it download the updates automatically. It will only install them when you login as an Administrator since restricted users can't install programs by default. I wasn't trying to knock Automatic Updates at all but it seemed funny to me when I could turn it on but I never seemed to get the updates. That was because I was never logging in as an Administrator and using RunAs to make necessary changes. Thanks Raymond for correcting me in comments (as I hate being wrong but I want to admit it when I am).
If you have 266 megs to spare and a decent broadband connection, don't wait for Windows Updates. SP2 is promised to be a life saver now and even though I've not touched it I'm dying to run it.
Thanks Rober for the post. I knew about automatic updates but without the MSDN link I wouldn't have found the version I prefer having.