Leaderboard hacking is more or less some hopeless guy attempting to re-energize his internet ego. But really this isn't a big deal. There's a helluva lot more glitches, hiding spots, overpowered weapons/perks, and people just taking way too much pride in noob tubing out there in MW2. People who take advantage of this often anger opposing players, therefore making everybody think the multiplayer aspect of the game is awful.
If you legitimately somehow got to the top of any online shooter's leaderboard, which is impossible but anyway, you'd be inaundated with hateful/"oh my gawdz!!11!!one hielpz meh wit mah skillz plox???/?" messages 24/7.
As for me, I own MW2 for my 360. I feel it's sad for anyone to hack or glitch in any way. All I care about is becoming a better player. But i have to admit it's frustrating when people do these things.
I like the game. If you don't, i could care less. It's my money. But seriously you have issues if you think blatant flaming of the game will get you anywhere. Really I believe a lot of people just hate the game either because it's so easy to, they are a troll, or they aren't good at it.
Online gamers are a weird crowd.
~waits for some angry replies~