XP SP3 is a solid release and everyone out there running XP SP2 should install it, especially if you are doing a new install. It is a great way to avoid 100+ updates post install, if you haven't slipstreamed them into your SP2 build already.
Things that could have gone better
#1. They should have released XP SP3 to MSDN and TechNet subscribers on the same day as the RTM announcement. This has potential to turn into a PR problem, especially after how Vista SP1's release was handled. I understand the technical reasons why Vista SP1 was trickled out, but as far as I know, the same situation doesn't exist for Windows XP. It is disturbing how quickly SP3 showed up on
Torrent sites.
#2. KB
888111 was originally planned to be included for support for HD Audio but the decision seems to have been reversed. If you are looking to get your HD Audio chipset working with SP3,
read this thread.
Update: I was looking at an old thread - KB 888111 is included with SP3. Never mind!
#3. FAQ.htm mentions
SP2 instead of SP3.
#4. Some setup text files inside the RTM build
are still labeled SP3BTA instead of SP3GDR.
With that said, enjoy the updated Remote Desktop Client (RemoteApps!), faster performance, network access protection, crypto updates, 1000+ bug fixes, keyless installs and other little polishes that SP3 has to offer. Don't let these little quirks scare you away.