One of the most famoust gaming sites which is very much liked by EA, GameSpot has posted a preview of Superstar:

"The show biz studio area consists of a series of open lots, much like the lots in the Hot Date and Vacation expansions. So, if you prefer to leave your sims at home and do some redecorating, you'll be able to wipe each of the studio lots clean and start from scratch by adding recording studios, music video sets, and sushi bars. Most of the studio objects will belong to one of three major themes: a music theme, an acting theme, and a fashion theme (including an actual runway). But you'll also be able to pick out new spa objects like mud baths and steamers to help relax and clean up your sims after a long day on the set."

There's some new information and details in the preview. You can read the complete thing, 2 pages, right here. For 3 trailers you need to be a GameSpot Complete member. You can find those right here.