We were there most recently Jan 2011, stayed for 3 nights after a week on the beach at Nirvana. We stayed in Moondancer, which is a 2 BR, but it's the same price as the suites if it's just two of you. If it's available, you could change your booking, you will get the specific room since it's the only 2BR that has that price.
We left a tip on our bill when we checked out, mainly because we were running out of cash at that point and didn't want to go to an ATM. I think I left $50/day. It would probably be better and cheaper to tip as you go.
We passed on the Cave dinner both times we stayed there, just didn't appeal to us with the high humidity, was more comfortable eating on the outdoor deck up top.
The rum bar was not open when we were there, heard they do charge extra for some of the rums. Wifi was spotty, but it was easy to find spots where it worked, mostly around the eating areas.
We didn't use the spa services.
There's not much to walk to, going towards town, the road is very busy and can be dangerous at times. You can walk to LTU, Rick's etc. if you want. I borrowed the bikes from them and rode the other way where it's quiet and peaceful with little traffic.