You go to see the Lion King for the choreography and costumes (which are amazing...) rather than for it as a show itself (the acting when I saw it was absollute crap, which could have influenced my view of the show as a whole.
You see Wicked for the all around great show. The staging has great moments (Defying Gravity), the music is very powerful and beautiful (For Good, anybody?), and the acting has so far been great as well.
So I would say that Wicked is the better show.
"If you can talk, you can sing...if you can walk, you can dance."
- T.K. Greene