Check your math.
The OP stated that the original purchase receipt for his BlackBook was $1300 plus tax. That's about $200 less than a "brand new" BlackBook. My guess is that it reflects both an education discount (which is normally $100 for this machine), plus a $100 old stock discount.
Also, the girl laid everything out in front of the buyer for him to see.
No shadiness here. No need for the overanalysis and pedantry.
The EDU discount from Apple is usually $1400 on a new Blackbook, but since this was a uni store, the pricing could easily have been $100 below this for no other reason than it's what the uni charges its students.
However, the interesting note is the date: 12/11/07. Since the girl did buy it on that date, there are only two things I can think of:
1. She knowingly bought an old stock machine and put it up on Craigslist as "brand new." Considering the fact that the OP had to see the ad after 12/11, I think any normal person would have assumed it was going to be an SR macbook.
2. The student store mislabled the macbook, and the regular Blackbook's pricing is indeed $1300 for that school's students. If so, this girl failed to read the UPC (just as the OP did) and then sold it as "new" without verifying the facts.
Way too much work to type in tags. They have this " symbol that is universally recognized as quoting someone.
Yes, but you're normally required to cite your source.
Ah... no. Two possibilities, both of which can be true or false, with third through N possibilities unstated. In this case... likely both that you present are false since they defy common sense.
I'd like a common sense explanation that doesn't fit the two hypotheticals I've already presented.
Words mean things. The machine was brand-new, not previously owned. There is not a "Mac Fanatic" special definition of the word "brand new" that causes a machine to become old when Jobs opens his mouth at a keynote.
Ok, we are disagreeing over the definition of "new" in this case. I think that if you are selling any electronic, "new" not only means "unopened" but also alludes to the latest edition/version of the product. "New" usually does refer to items that have been relatively recently introduced or haven't had much time to "age" as it were. You wouldn't describe a 6 month-old, unopened loaf of bread as "new" would you?
Again, words mean things. This is not a requirement. A Craiglist post of "Brand new black macbook never opened $1,000 have receipt" says EVERY she is required to say.
Perhaps it's not a requirement on Craigslist, but on the whole, sellers are required to post the exact specifications of their products. Even in MR's own marketplace, you must state the make of your machine. It's a common courtesy and uses "common sense" which you seem fond of.
Remember, I'm not saying that we ought to call in the authorities and have this girl arrested or something. My point is that she didn't do a good job of representing what she actually possessed.
"caveat venditor" can roughly translate to "It must be someone else's fault not mine!".
No, it means that people shouldn't attempt to defraud you (not saying this girl did, before you accuse me of that!

). Consumers can't be expected to research every possible fact for every possible product. However, because the seller is expected to know the limitations of his/her product, we can place responsibility on the seller to ensure that certain things are as they seem, and correct labeling is certainly one of those.
It's a horrible way to live your life. OP can be the guy who always blames the girl, the store, her parents, others on this forum for not warning him, Craigslist for not having a UPC verifier, etc., etc. or he can accept the responsibility for his minor mistake.
I don't want to go into a discussion about whether or not you think caveat venditor is a good idea or not (or how it relates to character building, because you'll find I do agree with you in certain areas), but I do blame both the OP and this girl. Both could have done something to verify the product. However, my natural inclination is to blame the girl more because she was selling the product. It's bad when a customer doesn't know what they're buying, it's even worse when the seller doesn't know what they're selling!
Once you understand that the machine was brand new, this is moot. Until you understand that, you've just got to keep reading.
There really isn't anything to "understand" here because dictionary definitions will not spell this out one way or another. This is a personal perception, and we'll likely never agree, so I think it's best if we move on.
He should have confirmed what the specifications were so that he knew he was getting the latest ones. Thats what I did when I bought mine.
Yes, it's what he should have done, but she should have also done it. Blame needn't be exclusively on one party.