It is no longer affiliated with Sony. I worked at Sony for about 10 years in their design group. I was running their San Francisco product and interface design studio when Metreon was being developed (part of Sony Electronics, not associated with Metreon). It was an ill-fated enterprise almost from the start. At some level, it is a good citizen of the city with good connections between the building and the adjoining Yerba Buena Park. But ultimately it suffers from exactly what you mention... the ambitions were that it would not be a mall but some sort of experimental entertainment complex. But in the end, it is basically a mall and not a good one at that. It is a real lesson in concept design... new concepts are great on the drawing board but almost always end up being compared to something that already exists when its launched.I really appreciate Andy's unique insight. All of this puts me in mind of Columbus' ongoing woes with City Center (pretty good summary on Wikipedia. I know that there are a number of proposals being vetted right not for what to do with City Center.
Anyway, only the theaters performed well financially (which ironically generated little revenue for Sony) so they finally sold the complex to a company that owns a bunch of malls across the country. I think they sold it a couple of years ago. The only remnants of Sony are now the SonyStyle store and the Playstation store as tenants. The new owners will probably have the same struggles unless a major renovation is done.
I'd say, let the Metreon stand as a cautionary tale: even with heavyweight financial backers (hello, Sony?! Microsoft?!) and in the middle of an undeniably first-class American city, the 'urban mall' is a tricky mix to get right.