Half of me is screaming, "Awesome! Lions! They're just on the other side of this glass! You're not so tough now, are you Mufasa? Huh? Huh? RAWR!"
The other half is realizing truly how little space these animals have to move around and how they are surrounded 24 hours a day by crazy tourists that they would eat in retaliation if they got the chance.
Overall it's sort of a cool idea, but I feel pretty bad for the lions.