I watch K-ON! when I had nothing to watch at that time. I was attracted to the drawing style (the one on the official site) and that it'll be animated by KyoAni.
For the first glance, I thought "Whoa, Haruhi-themed with Lucky Star's design". I was expecting that it'll be more music-centric, but apparently that's not the point XD
Still, I like how this anime can influence our emotion.