We did AK in July of 2011. Amazing! We're doing the Western Caribbean for spring break this year and have done the Bahamas. The Caribbean is always what comes to mind when you think about cruising but I have to say that I'm hoping to enjoy this one as much as the AK one. I think the main difference will be that on the AK cruise there's always beautiful scenery to behold along with super calm water and wildlife to be seen off the ship. Sailing the inside passage is like sailing through a river. On the Caribbean it'll be like the Bahamas, water for scenery until the ports. For me, I think of AK as a once in a lifetime deal although we're hoping to return. The Caribbean for lots of folks is also once in a lifetime. I think you need to consider the experience factor; the ship size, the ports visited, the excursions, the variation of the excursions from port to port, the weather conditions, when can you cruise (AK is summer only). You can also consider where does the cruise sail from. Our AK cruise sailed from Vancouver. We had 2 fantastic days there before the cruise, a place we wouldn't have gone to otherwise but now would like to go revisit. Good luck with your decision.