The New York Times spent 36 hours on St. John. And an exhausting time was had by all, I'm sure.
Start at Joe's Rum Hut at Wharfside, then Woody's (where they actually went to eat!!. Then on the second day, a picnic to go from Dolphin and snorkeling
at Watermelon Cay, lunch at Skinny's in Coral Bay, shopping at Cocoloba Center, Miss Lucy's for dinner. Sunday, Chilly Billy's for brunch and shopping in Cruz Bay.
I'd be pooped.
Suggestions for a short-term stay like this: Caneel Bay, Westin Resort, Maho Bay and Cinnamon Bay. The article is online at http://travel2.nytimes.com/2006/02/24/travel/escapes/24hour.html?incamp=article_popular_5