I haven't seen it yet. But it's what I intend to attend this weekend.
And yeah, I know the previews make it seem kind of silly. But it's based on a novel by Neil Gaiman, who may have hordes of annoying neo-pagan hippie-chick fans, but that somehow doesn't prevent him from being a good writer anyway. Gaiman is actually a perfect gateway drug for use by male geeks who want to lure women into their world -- tempt them with images of unicorns and faeries, then before you know it, they're reading Sandman, and you can be all, "Ha ha! You're reading a comic book! Now, if you like that, maybe you'll like...[some comic she wouldn't have looked at before.]"
Anyway, the last movie Neil Gaiman wrote the script for was MirrorMask, and it was amazing. Go rent it now, in fact, or buy it. It didn't get a wide release and made almost no money, but you'll love it, probably. [And the Henson company can quote me on that]
This movie involves a falling star, and wicked witches, and yes, a unicorn. Looks kind of like The Princess Bride, and is directed by Matthew Vaughn, whose Layer Cake was -- despite the awful title -- one of the better BritTarantino flicks (and made people believe that Daniel Craig could be Bond), and whose X-Men 3 never got made because he dropped out and was replaced by Brett Ratner.
Read Robert Wilonsky's review of it here. Robert's a tough critic, so even the fact that he only kinda likes it is good enough for me.