Battle: Los Angeles doesn't try to be anything its not. It doesn't strive for Oscar-worthy dialogue. This is the kind of film thats been missing for a long time: a fun silly popcorn flick that doesn't try to nod to every other film in its genre. Its Marines vs Aliens; everything blows up, there are lots of 'hoo rahs,' alien ambushes, and vaguely patriotic music. And it is GLORIOUS! Worth full ticket price.
Sherlock Holmes was a fantastic movie and completely worth your money. A few minor liberties were taken with the characters, but overall Robert Downey Jr & Jude Law's portrayals of Holmes and Watson were brilliant, and Guy Ritchie's direction was refreshing.
Avatar is pretty. Very, very pretty. Jim Cameron and crew did a brilliant job with the effects, to the point that something will jump out at you looking like rough CG until you realize EVERYTHING you've been watching is CG.
Still, there are only about 2 shots of 3D that make it worth it. And since this will be the penultimate 3D movie for years to come, save your $5. Watch it in 2D. The storyline is completely cliche, the dialogue is predictable and clunky, and yet its such a fantastic visual masterpiece that you won't care.