I didn't realize until I got home, but the really cool themed 3D glasses I picked up to use were technically for children, though they did fit me fine. They have a little Simba on the front and one of the arms says "The Lion King 3D". I thought they were really cool!
My total opinion: It was cool to see The Lion King on the big screen again; when it came out in 1996 it was the 2nd movie I had ever seen in theaters and my sister's first. The 3D was a unique way to see the film, but it did little for me honestly. If you are a big Lion King fan or just want to see the film on the big screen again, I say go for it. Otherwise, I would say put the $13 a ticket towards something else, like buying Lion King on Blu-Ray to get all the awesome features that comes with that, or put it towards your next Walt Disney World vacation and see the Festival of the Lion King show.