Windows XP SP3 in Q2 2008

The third and so called final service pack for Windows XP is coming soon. The second quarter of this year to be exact. Not sure it if its a really necessary update, but it would still be a good idea to get if your a hard core XP user not wanting to switch to Vista. The update is suppose to be a whole bunch of smaller updates that have been released over the years, rolled into one. I personally have two computers, one running XP and the other Vista, so I'm good either way. But I still plan on updating the XP just in case. But speaking of service packs, did one come out for Vista yet?