I get the hate and agree that this movie left quite a bit to be desired. There was so much territory unexplored and basically Alice in Wonderland (and fragments of Through the Looking Glass) became another vehicle to sell "Johnny Depp and Tim Burton do something together".
However, for those suffering from massive disorders of psychotic thought, Johnny Depp's performance is eerily spot on, and I was nearly moved to tears (and rated ten exactly for) at the line "It's awfully crowded in here".
See it if you love Tim Burton or Johnny Depp or wonder what Disney's canon post-animation for Wonderland is outside of Kingdom Hearts. Don't see it if you want to see Carroll shown any real honor on the silver screen.