and
www.cruisecritic.com. Princess, Holland and Celebrity are all about the same caliber, and in my opinion, WAY better than Carnival and Royal Caribbean. That being said, if what you're after on a cruise is lots and lots of activity (see ASUADPi) either Carnival or Royal Caribbean should work. I'm surprised about the comments about no on-board activity on a port day, but the short duration (3/4 days) LA departure cruises are weird at best and to be avoided if you're not there for heavy duty partying. Royal Caribbean has recently repositioned themselves as the market leader in family cruising, so you can plans on lots of kids and lots of activity poolside. NCL is considered lower tier than Carnival, but I must admit the most fun I've ever had on a cruise was on NCL. I personally won't cruise on Carnival again (twice was 2 times too much). I prefer Princess, but I'm here to tell you that it's worth sailing on Holland if ONLY for the bread pudding. Yes, it's that good. Everything else about their cruises is good too. But the bread pudding...
eta/oh, I just did a quick check of cruises for Thanksgiving and there are still some great rates available out of New York, Baltimore, Florida, San Juan, Galveston, New Orleans... lots of choices!