A group of us were there in 2006, I can't imagine it's changed much. It's a really quiet, peaceful area. Probably more goats and roosters than people. No crime that we heard of. The Villa we stayed in didn't even have exterior locks. Manager said they've never needed them. I left all my u/w video gear, laptop, lots of cash out in the open all week, nothing was touched.
We did all our diving with DiveBVI. They were great. Just a nice group of people to dive with. One of the few dive outfits that really provide the service they describe on their site, we dropped our gear off the first day and after that everything was stored and ready for us on the boat all week. VGdiver here is Jeff, their GM.
Took us to all the good dives, the Rhone, Indians, Dogs, etc. They have several dive boats including a new (2006) 46' Newton. They pickup at several locations on VG, their main shop in "town", Marina Cay (island) and Leverick Bay. Second shop at Leverick Bay also.
Other must-do's on VG. The Friday Night Buffet at Leverick Bay Resort. Everyone goes, tourists, locals, sailors etc. Do dinner one night at the Rock Cafe outside on their multi-terraced patio. Pricey but worth it.
And of course there's snorkeling at the Baths.
Virgin Gorda is really spread out so you'll want a car. Most of the activity is near town to the south or the far north end. The middle is just a few resorts along the water and private houses. Lots of open land.
It's a sailing destination first so a lot revolves around that. You can also daytrip over to Tortola - at least when we were there, it was possible via the ferries. It's also doable to fly in/out of St. Thomas and take the ferry over to VG. The ferries are fast and run often.
PM if you have other questions, I may not follow this thread.