It's a metal "basket" with a bottle of champagne (supposedly you can request or exchange for sparkling cider), a photo album picture frame, and a small box of chocolates. It normally retails for $59 (you can order it through their preboarding gift catalog).
If you look up at the top of the main cruise line forum, there's a thread that says "look here for usuful cruise info. There's a link inside to anohter thread talking about the REAS. There's pictures and everything about the basket.
This gift basket is waiting on your bed when you board the ship on the first day It's hard to see in this pic, but it's in the center, surrounded by the other gift baskets we had ordered for our sons:
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