I get tired of the show pitting Rachel against Mercedes. They've done this so many times in past seasons. They're good friends, then they're rivals, then they make up, wash, rinse, repeat.
Personally, I can't stand Rachel's voice or her personality.
I have to wonder what's up with Mercedes saying she's not feeling well. It only seemed to come up while she was practicing. Is it an excuse or is there some big storyline coming up about her getting a serious illness? Maybe she has mono.