I was required to setup serveral Windows XP workstations for a client, which required me to join them to the domain. I noticed upon moving the workstations into the correct OU on the server that, after a GPUPDATE /FORCE and reboot they would just skip over the software installation policies deployed from the server.
Cut a long story short the problem was with the group policy time out. A simple reg hack did the trick, which i rolled out through a startup script.
Windows Registry Editor Version 5.00