Mac: Battery Myths

Hey guys, I've been reading up on Lithium-Ion batteries and how the the Mac operating system handles it; but there are still a couple questions that are quite ambiguous.

I was wondering if any of you would be so kind to clarify things, once and for all! So here they are:

- Nice guy OS X displays 100% charge when the battery is really at 80%, for more recharge cycles

- When fully charged and plugged in, your Macbook does not take energy directly from the outlet, but instead depletes to ~90%, then charges it back up, repeating the cycle (while still displaying 100%)

- When you're at 0%, you're really just at <10%, so functions like time and geo-tracking don't get disabled

- Instead of keeping your Mac laptop plugged in all the time, you should let the percentage stay between 30-70% to lengthen lifespan of battery

Thanks for clearing things up, been dying to know for awhile now, to avoid inconvenience and prolong the lifespan of my MBA. Thanks again!