computeropponen: This is an old discussion; it seems that 90% of the top-rated 100 chess players here on BK are using software (in other words: cheating), as they are just too good to be true.
I have talked with one player that is a verified International FIDE Master and he barely can make it into the top 50 players. So either all world class chess players are here under secret IDs (including all the dead ones), or there are cheaters between them.

Again, note that this is an ongoing (and by now boring) discussion on all gaming sites; some claim that the rules don't disallow software so it is not officially cheating (correct), some claim that it is a lie and that they are just that good (hard to believe for me), and some just never answer if asked.
And some might be really that good.