This is only for the XP users, be it Home, Pro, etc. There is a major security vulnerability that is fixed in SP1, I advise you to upgrade before idiots out there start using this security hole.
Here's what Steve Gibson of
http://www.grc.com has to say:
Attention Windows XP Users
A little-known but critical vulnerability exists in Windows XP.
It has recently been repaired in Service Pack 1.
This vulnerability allows the files contained in any specified directory on your system to be
deleted if you click on a specially formed URL. This URL could appear anywhere: sent in malicious eMail, in a chat room, in a newsgroup posting, on a malicious web page, or even executed when your computer merely
visits a malicious web page. It is likely to be widely exploited soon.
This vulnerability is so dangerous that it would be irresponsible for me to say more. Microsoft has known of this problem for months and has, inexplicably, done nothing before now. Although XP's Service Pack 1 is not small (approx 30 MB for express installation or 140 MB for the network install), and even though a much quicker and easier solution to this problem exists, the only thing I can safely recommend (without revealing too much) is to urge all XP users to somehow obtain and install Service Pack 1 immediately. (If you have a slow Internet connection, perhaps a friend can download the executable Service Pack file and burn it onto a CD for you?)
This problem does
not affect any systems other than Windows XP. If you have any friends or co-workers running Windows XP, please urge them to update their systems' too. Once the details of this vulnerability have leaked through other channels I will provide additional information. To visit Microsoft's Windows XP Service Pack 1 download page:
CLICK HERE