People think that it has been patched, it hasn't.
The Prestige glitch cannot be patched since you are pulling out the ethernet cable, you are not doing something in-game to cause the glitch.
Here is a quote which came from a player named 'thiels2' who say's he can do it, he also explains how to do the glitch.
Originally posted by another user
Tutorial :
1.Get to 55 able to prestige.
2. Enter prestige and wait 3 seconds then pull out ethernet cable.
3.Turn off PS3 by front.
4. Plug cord back in and turn on using front.
5.Log into the user that you did it with.
6.Go to game.
7.You should be level 1 next prestige.
8.Quit game.
9.Delete the user that you did it on.
10. Create a new user and re-create the account you just deleted.
11. Log in and go to game you should be 55 next prestige.
WARNING : Make sure you know your details before deleting user.
Not sure if this works past 55 unprestiged, have not tried.
Again like COD5 it may not work on everyones account.
If anyone is having trouble PM and i can do it for you.
I myself havent tried it though, I get bored very easily when I've completed a game so I just do it without glitching. A few people have tried that way and have said that it works.
Hope my post helped someone, if it did then please +Rep or click 'Thanks'!
That way I know I'm helpful and that I should carry on..