Five years ago the advice would have been very different, but nowadays in the hotels you'd be forgiven for not realising it was Ramadan. I was there last year and all the pool bars, etc. were open and serving alcohol and food was being served poolside (this was the Westin, but I can't imagine the W being any different). Brunches still run on Fridays (although they close the outdoor spaces). The big difference is there's no live music anywhere - that's about it.

If you go to the mall then all the restuarants and cafes have thick blackout drapes hung in front of them during the day and they don't permit Muslims to enter during daylight hours - but tourists can go in and the restaurants are all running as normal inside (though in the mall there's no booze served regardless of the time of year).