Should i leave the charger connect to my macbook all the time?

I do with no harmful battery effects. Been doing so for 5 years now.

Just be sure to do the "mobile device" thing every now and then to exercise the battery, add a few charge cycles per month. Else when you need it may discover that the battery runtime won't be what it was when new.

Apple has a battery usage recommendation thing, and it tells you what a full use is after you charge it, and like how often you should recharge and when. again, its just a recommendation that they make.

to my experience, leaving it always in decreases the amount your battery can maintain its full charge potential.

I have a 2007 ver. MBP and this one can take off the battery. so in my case i take it out and just leave the A/C on it 24/7. but for the new ones, you cant take out the battery THEREFORE they recommended something like "dont leave it in, just charge when you reach 20%" and then use again."

seems like i went in circles, but its definitely in a forum post somewhere.

gluck

here is what Apple has to say: http://www.apple.com/batteries/notebooks.html

BINGO

welcome.