I've stayed at the JW several times but only did the Cloub Club one time. At $50 per night, per person, you need to be a big drinker to recoup the costs. The breakfast is nice but as plat, I've most recently gotten the breakfast buffet at the Blue Sage for free. The appetizers and desserts are nice but many nights we weren't in the hotel in time to enjoy those.
You also have access to a PC & printer there and can check out books, games & CDs for free. Spa access is part of the cloud club pacakge. They offer concierge services and guarantee you access to spa appointments and tee times within 90 minutes of your requested times.
You get a small gift bag, special toiletries if I recall. No children permitted these days either.