While we've seen attractions come and go on Singapore's Sentosa island over the years, Resorts World Sentosa's gambling its $5 billion investment has staying power. Just opened are four hotels -- Crockfords Tower, Festive Hotel, Hotel Michael and a Hard Rock, which together offer 1,350 rooms. Next up is a retail and dining strip called Festive Walk, while Universal Studios theme park and a casino are in the offing.