Ok, thanks folks.

We are indeed going to the US Virgin Islands. So I should probably try to get a credit card.

Looks like it's now 48 months between signup bonus points, but I don't believe I've had a business card for that long (thoughI have had a personal one). I don't see any mention of 48 months (or even 24 months) for the Barclay Aviator cards (which also get the free bags and a nice signup bonus).