Ok.. I'll give u my list before Anne jumps in and fills the entire page<VBG>
Royal Caribbean.. Nordic Prince, Majesty of the Seas, Grandeur of the Seas, Rhapsody of the Seas (twice), Legend of the Seas, Vision of the Seas
Princess... Grand Princess, Ocean Princess
Carnival... Destiny ( 3 times), Triumph, Ecstasy
Holland America... Veendam
Celebrity... Century, Mercury
Seabourn.. Seabourn Sun
Coming up (thankfully soon)... Celebrity Millennium 10/13, Carnival Sensation 11/19
Personally I think it's hard to have a favorite cruise line. Don't think any are really consistant enough to easily say this line is the best.
And it's getting harder and harder to even name favorite ships. All of my cruises have had most memorable moments, which I guess is what keeps me so hooked on cruising.