The problem I have with this is unlockables. People like me have cheated over the years to get unlockables. People like me enjoy achievements, but wouldn't cheat to get achievements. Unlockables however, extend the life of a game, and sometimes even make a game many many times better. Although I don't have one yet, I almost always end up getting an Action Replay or something similar for each system I own.
I beat Dead Rising. Game was hard as nails but a lot of fun. I want the costumes and unlockables available to me.
Here's an offender from Nintendo: Smash Bros Brawl has tons of characters, music, and stages locked away. They used an encrypted save so I can't even download anything. Great.
I'm not in grade school, middle school, high school or college. I try to maintain a social life, I have a girlfriend, I'm continuing my studies, I literally do not have the time to unlock everything. I used to love RPGs and yet these days I just don't have the time for them. I just want to relax, pick up and play these days.
No company should be telling me how to play my game if I'm not screwing anyone over. My point is, I should be able to unlock whatever content I want without repercussion. Fuck MS's TOS and fuck developers who tie achievements to unlocked content. Years ago I had plenty of time to unlock things in games. These days it takes forever to unlock stuff because games are just way too long.
You want to reward me for a job well done? That's what achievements (or trophies in SSBB's case) are for. Don't tie them to unlockables.
And anyway, what do high gamerscores MEAN anyway in the grand scheme of things? Gamefly every sports game on 360 and you can probably get 100,000 points in a weekend. It's those really hard ones in specific games that actually show off some talent.
I don't care who I should be pointing a finger at... developers, microsoft, or the cheaters trying to inflate their gamerscore, but I do know one thing, they're all assholes and this policy would make me look bad.