Most of the major online sites are legitimate and honest. Unfortunately, due to the attempts by US government to drive the industry out of business and criminalise it, there is no reputable official overseer in place to keep an eye on things and regulate them properly, so there is always going to be some doubt, especially in the light of the recent scandals involving Absolute Poker (where a disgruntled former employee exposed a back-door in the system which allowed people at the company to see player's hole cards and cheat them) and Ultimate Bet (similar deal, only this time the person alleged to be benefitting from the cheating was the site's owner himself, Russ Hamilton!!!). I play a lot of online poker, and have faith in the two biggest sites, Full Tilt and Pokerstars... nothing there has ever made me doubt their integrity. But it is easy to see why people have their suspicions, and I cannot categorically say that the sceptics are wrong, however much I wish I could. I can however say that I am extremely sure that the RNGs (the system that generates the cards) are honest and unbiased... any bias in this would be obvious to any experienced player who plays on a site and keeps a log of their hands on Pokertracker or some similar software, and would have been exposed by now. Any cheating that may have gone on or still be going on will revolve around the sharing of hole card information rather than "rigging the deck" in any way.