Anyone tried these yet, my systems has been very reliable but I'm always game for anything that might improve responsiveness, etc...

Asked and answered, KB941649 prevents my systems from booting. Had to toss in the install DVD and do a restore to get back in to my PC. Have to dig up a link and file a bug report with MS, might wanna' let these cook a little longer before you try 'em. That said, if this were XP I'd like be re-imaging right now, nice that Vista's recovery worked so seamlessly.