I have a few backed up games an ive noticed since the update that if I unlock an achievement in a backedup game it will show on my gamer card on my xbox but when I sign into Xbox LIVE an then check Xbox.com my score hasnt changed! However if I play a retail game and unlock an achievment it shows on Xbox.com!!!
Example, I had 340 points in Assassins Creed(Backup) before the update, now I have 940 in assassins creed but when i sign into Xbox LIVE an then check xbox.com I still have 340 points. HOWEVER, I played a retail guitar hero 3 an unlocked a few achievments an this shows on xbox.com!!!
Obviously miscrosoft has made it so copied games dnt have their scored updated on xbox.com. However, they still show on your 360, e.g. my score on xbox.com shows as 52,245 whereas on my xbox 360 its actually 54.455. Backep up games no longer have their scores updated online on xbox.com.