Japanese mixing English into their songs, esp. in anime, kind of screws it up for me. I don't watch anime intros, subbed anime (sometimes), or Japanese songs (sparingly as that is) to hear English! I wanna hear the ORIGINAL language. Japanese singers especially need to quit acting like English is SOO cool. It's just another language that happens to be the lingua franca (if that's the correct term) in the current era.

On the flip side, some English in Japanese, like on signs, can be quite helpful to a non-speaker like me.