This has nothing to do with cheating online. This news only pertains to people who have downloaded someone elses gamesave with one of two intentions. 1. skip a part of a game you either don't want to play or can't beat(what if you wanted to just see the ending of a game you rented and didn't have enough time to master a partiulcarly hard level?) 2. Artificially pump your gamerscore.
Now I did this for one game, for reason number 1.
I can't speak for people under number 2, and personally I think gamerscores are stupid, never once went out of my way to get them, never will, and would never waste my time downloading a save just to get a higher gamerscore, in fact I'm actually glad MS may wipe my gamerscore, I think higher gamerscores make you look a little patheitic, they only attest to how many actual hours you've played.
Secondly if MS wants to from this point on threaten this action, or just make it harder, fine. I'm fine with that. They already made it nearly impossible to use gamesaves, so it's not that easy to get away with. Or just take away achievements you didn't earn, that's fine too(I don't know how they'd even know that.) But to 'punish pay customers with a freaking list, seriously? Do they honestly expect to keep these people as customers?