Thanks Hirakata. Possibly one of the best explanations.
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BTW, I chatted with a rep on Apple.com/store cause I had nothing better to do and this is what he said:
Him: Oh, well if you bought new from us here online, it will come with Mountain Lion 10.8 on it!
Him: Solid, you will have the up do date software on it when you open it up then.
me: the description when I was Checking Out said OS X. It didnt specify Lion or Mtn Lion.
Him: Oh yeah, any bought July 16th or later will have it.
Seems to conflict with what others are saying. Thoughts?