He is not as excited about Kermit the Frog as he is about Lady Gaga, but I think Bow is a definite fan of the little green guy.
What is the possible appeal of a muppet to a chimpanzee? Clearly, the muppet is not real. Bow knows that, so that even in relatively violent scenes in which Muppet bodies are flying, Bow does not get upset, but he is nevertheless amused enough to keep watching. On the other hand, he seems to understand that the Muppets stand for people, and he likes them for that reason. Also, he enjoys the music, which is calm and pleasant and not too challenging.
For anybody who thinks chimpanzees are incapable of abstraction, and that they look only to facial and other non-verbal cues when interpreting language, consider the Muppet connection. Bow understands Kermit, but Kermit has a really limited set of facial expressions. Muppets are just abstract enough to require imagination and linguistic capacity, but concrete enough for us all to get what it's about.