I would love to see Mac enabled "old" games.
I bought a Mac Mini (2010 8GB) because my Windows machines (XP,Vista, 7) all keep crashing, and OSX is stable, and the Mini is the only Apple I could afford. However, trying to run a PC game, even Beneath A Steel Sky, under Parallel's Desktop made the Mac Mini grind to a halt. Using a Wine wrapper would probably work much better with limited resources. I've had little luck working with Wine wrappers or even DOSBox myself.
So even though I still have many old games, some on original disks that I don't even have drives for anymore, I would be willing to purchase them from GOG. I have only purchased a few, so far, because my Windows machines don't stay running long enough to play the games. Maybe Windows 8 will be more stable.
I did buy (sadly not from GOG) the Mac version of The Secret of Monkey Island, and it played wonderfully on the Mac Mini.
Programmers used to talk about how programs should operate in a "black box" so that they ran the same no matter what hardware was used, and never became lost do to changes in hardware, operating systems or even programming languages. It's too bad this is such an impossible dream in reality.
On a side note, I prefer "old" games due to better quality, and because new games are too expensive and require expensive hardware to run.