I have chimed in quite a bit on this issue, but once more won't hurt .. We (me 43, DW 44, DD 16, DS 8) have sailed DCL twice, with a third coming in November. Have also sailed RCCL-Voyager class ships twice, with a third coming next October (or earlier if the gods are kind).. It all depends on what you want.. You really can't make a wrong decision... I do think that the RCCL ships have more activities, especially for adults. (more lounges, casino, art auction, many more sports-related activities). DCL has , well, Disney !! Great shows, great movie theater, larger cabins ....
Price usually favors RCCL, and there are 4, soon-to-be-5 ships in the class doing 7-day voyages with three/four different itineraries as opposed to DCL's 1. And next year the VOS comes to NY for a 9-day journey to the Western Caribbean (good for us northeasterners).
I have offered my comparison of the two in the past, and still do .... e-mail me for the web site address....
mac_tlc