Rosario + Vampire is a great show. The best part in my opinion is that it doesn't completely follow the manga (which most anime do). The characters are great and there is a lot of humor in the series. Every episode has a "monster-of-the-week" episode and it always has a funny struggle between the girls for the main characters love.
The only sad part is that since season 2, the anime networks in Japan started to cencor the anime with annoying teddy bears.
I hope that after season 2, another season will follow it. I got redrawel symptons after the last "break".
I give this show an 8.5/10