Katy Perry tease

TORCH SONG: What is Katy Perry setting on fire in this mysterious snippet, which bowed on VEVO today? Maybe we'll find out when "Roar," the single teased in this beguiling micro-clip, arrives on 8/12. Of course, the announcement that her upcoming Capitol album would be called Prism and would street on 10/22 was made somewhat less subtly, with a gold 18-wheeler rolling through L.A. Meanwhile, a UMPG truck made entirely of weed began crumbling on the 405 earlier this morning, snarling traffic and drawing a SWAT team. (8/2p)