@jcraig - I am with you. The differences are very intriguing. I would have to guess that the lute came along before the guitar, since during the Renaissance, lutes were a common instrument.
My friend is a music major, and he owns a lute. I play the guitar, but I was still very confused by the notation that was used with the tablature. He tried to explain it to me a little, but it is hard to break old habits.
I think using the letters to represent frets instead of numbers was the hardest to get used to. It is also a lot more difficult than you might expect to fingerpick and be able to play both strings at the same time. I guess I now know they're called courses.