The main difference between Hollywood and Orlando is that Universal Hollywood is an actual working studio, and the studio takes precedence over the theme park. The studio tour in Hollywood is very cool. However, the park is much smaller and has many of the same attractions as Universal Orlando. It is very nice but IMO it will be a letdown after Orlando. You could also take studio tours at Warner Bros, Paramount, and Sony, which are cheaper than a Universal ticket and the actual tours there longer.