Zwiebelchen
Fractal Fanatic
Probably the very same. Instruments are not like wine, even if most people think they are. An aged and vintage instrument CAN sound remarkably 'better' than modern, well made instruments. But then again, this is just because 'different' and 'vintage' together equals 'better' for most people. I'd say the majority of old, vintage instruments haven't aged that well. The wood gets worn-out, the frets aswell. The older a guitar is, the more likely it is to take a hit or two, so the neck won't be as straight as it was when it was new.
Then again, wrinkles sometimes do add character...