Whether it's worth skipping a year of vacation is subjective. Having said that, we have been to WDW several times in the last few years and finally did a Disney cruise last May.

Our 10 year old son thought the cruise was the best vacation he's ever been on.

I liked the cruise about equally as well as WDW. But we go to WDW in the off-season (when crowds and temperatures are lower) and stay on-site in the nicer Disney resorts (and eat in the nicer Disney restaurants). So the way we do WDW is way more relaxing (and expensive) than the way most people do it.

Alternatively stated, I think a Disney cruise is superior to WDW unless you go to WDW in the off-season and go "all out" (stay and eat on-site at he best places), in which case they're about equal. Surprisingly, a Disney cruise tends to be somewhat cheaper than an "all out" WDW vacation, so IMO the cruise is actually better bang for the buck.