Join Date: Dec 2003
Location: Redondo Beach, CA USA
Programs: UA 1KMM, Bonvoy LTE+A, HH D, Nat'l EE, Hertz Plat, Avis PC
Posts: 3,716
Upgrades are rare (almost unheard-of) on Disney, as their ships usually sail full. Check the prices from various sources (Costco, AmEx PTS, etc.), calculate the value of the bennies you get from each, and choose accordingly.
And to come back to the upgrade issue, don't book any cabin you wouldn't be happy sailing in. Too many people book on the cheap, mentally telling themselves they'll get an amazing upgrade, and then don't enjoy their cruise when that unrealistic expectation is not met.