The thing about bonuses is that there are ALWAYS terms and conditions that must be met.  Usually players must wager a minimum of 30 times the bonus balance prior to making a withdrawal from a  cash account.  The bonuses are a great way to get some extra cash to try the online casino and find out about the software, atmosphere, graphics, etc... , but keep in mind that Ts and Cs must be met BEFORE attamepting to withdrawl funds.  Withdrawing before the Ts and Cs are fullfilled may jeopardize the winnings.  Remember, a casino is more than happy to deny a withdrawl if their terms and conditions are not met.

This article is ment to inform, not to frighten.  Go for the bonuses, have fun and always understand the Ts and Cs.