Actually, I think Apples to Apples, Virgin is the same or less. I like the fact that all Dining and Gratuities (including those at the bar, etc.) are included. Also, the food on Virgin is way ahead of RCCL IMHO...
I think that the issue for a number of people is that you can sail one of the new CCL ships (Mardi Gras, Celebration, Jubilee), Virgin, Princess, or Celebrity, etc. for less than sailing on RCCL and get more for your money.