No this is not a scam. The difference, ripple is controlled by a company just like paypal, payza, moneybookers, libertyreserve, webmoney, perfectmoney. They are created for profit.
Ripple is no more than a promise.
And since (amost) everyone here is just trying to get richer instead of backing up a great alternative to bank world-control, Ripple is bound to be just another villain's nest... Sadly.