Imagine you are going to a company christmas party and you'll be right on track or a nice wedding if that helps. The men commonly wear dark suits and you will see a tux here and there. Don't stress, your on vacation!
You see a lot of different things. I have worn niced black slacks and a glitzy top, or a plain black dress dressed up with jewelry. I have seen girls in their prom dresses and something "mother of the bride" would wear. It's not all that formal. Don't worry about it, just have a good time.
Carnival is not as lax as some would have you believe. The jokes about formal jeans and a clean teeshirt are just that, jokes. Compared to NCL, which has no formal nights. Princess, being a bit more upscale, and catering to an older crowd is much more formal. It is rare on Princess that you see anything but tuxedos and evening gowns.
__________________ Cruising since 1987 (With a list to long to fit here)
[b]Next Cruise: Voyager of the Seas - Transatlantic November 29, 2008 on the Voyager of the Seas