Probably the biggest IS news item recently is the discovery of a fairly serious vulnerability in the venerable Adobe Acrobat "PDF" file format. Briefly, it's one that doesn't require you to actually do anything for the vulnerability to be triggered, other than have Windows Indexing Service enabled (which I believe is turned on by default in XP). Even if you don't have that enabled, merely passing your mouse cursor over the file in Windows Explorer could still trigger the exploit. Now, this is only if you've actually downloaded a PDF that has been hacked to have this kind of malware inside of it, but AFAIK this is a sort of a new thing, where you don't even have to open the file to get the bad stuff happening. Note that this vulnerability exists on MacOS as well.
The morbid details are here, or you can see the sanitized Adobe discussion here.