Both have pluses and minuses.
If a game is installed on my hard-drive, I vastly prefer digital. Switching games without switching discs is nifty. The downside is that I have a slow internet and it can take all night to download a game, so even if I buy a digital game, I can't play it until the next day.
Physical games you can resale but digital sales are usually cheaper so I guess that evens out somewhat.
I guess, really, I don't care that much. The game is the important part, not the medium through which it's delivered.