Well, I do not know if anyone is cheating. Common sense says yes, not because of the scores but because the programs are out there. They make marital aids the size of a driver head. Do you know why? Because, good idea or not, right or not, someone buys the damn things. And as sure as there are cheat programs out there for WGT, some people will use them. But, I have no knowledge of anyone cheating, and firmly believe the best players are just the best players.
Having said that, it seems to me that if WGT did catch someone for cheating, by means other than profound idiocy on the cheater's part, announcing it publicly, along with the banning of said player, would be a nice deterrent.