The above screenshot is just one example of the highscore manipulation that's been going on the arcade. After a brief staff discussion, we decided that from now on such behavior will be dealt with. Besides erasing their highscores all across the boards, cheaters will have their arcade access revoked, as per
the new rules.
Personally, I feel that lame cheating like that goes against the spirit of our forum. The custom challenges, the hidden star awards and the achievement signature bar - all of these are based on good faith and they rarely see abuse. The arcade works much the same way: with virtually no cheat-proof system in place, it doesn't take uber-hacking skills to manipulate the scores, yet most of us don't feel the need to do so.
So it's a bit unfortunate that we have to spell out this obvious rule, but if that's what it takes to deter a few bad apples from ruining the fun, then that's what we do.