The main attraction at the Metreon is the movies. There are 16 screens, including two IMAX theaters.
It's downtown, on the corner of 4th and Mission, which is one block south of Market Street. It faces Yerba Buena Park on one side, and you can see some fantastic views from the Metreon's upper-floor plate-glass windows and terraces.
The theaters are comfortable and well-maintained. In general, it's a good place to see movies. But it can get very crowded on peak times, like on holidays, and popular shows may sell out.
The complex itself is, in my opinion, very garish, with lots of loud colors and blinking lights. It makes me feel as if I'm on the inside of a pinball machine! But I have to admit, it is an experience, and I think it might be especially appealing for kids and teens.
There are also restaurants and stores and arcade games and special exhibits and places for coffee and for dessert. One warning -- if you buy a coffee at Starbucks and bring it upstairs with you to the movie theaters, they won't let you in the theater with it! They'll say you have to finish it first. It's quite annoying to have to gulp down a hot cup of coffee, especially if you're running late for your movie. The reason, as I found out when this happened to me, is that the management of the movie theaters (AMC) is different from the management of the rest of the complex (Westfield), and they don't want you bringing "outside" stuff into the theaters -- even though you bought it in the same building!