Battery on Unibody Macbook Pro 13inch

Hi,
I've read alot of the posts regarding the battery life and whether you can leave it running on AC power after the battery fully charged. Quite a few contradicting points that confuse me. - which brings me to the universal question of whether can we leave the MBP running on AC power even after battery is fully charged.

My situation is as such - I tend to watch a lot of streamed online videos. Probably 2 and a half episodes (approx 40 mins each) can drain a fully charged battery. On other occasions, I do light surfing and photo editing.

Can I leave the AC on after its fully charged when I watching the streamed videos?

Welcome to Mac Forums.
Yes you can leave it on AC fully charged.... you should leave it on AC as often as possible.
The battery life is mostly about charge cycles.
The other thing to do is calibrate your battery around once a month.
Apple Portables: Calibrating your computer's battery for best performance