I do both. I play face to face at school, but I have friends who have friends who have already graduated and are spread out across the country. So we play with Fantasy Grounds and Skype. It may not be exactly the same as a face to face session, but I certainly disagree with the folks who say it isn't a social activity that way. We make the same Monty Python quotes in there that we made when we were all gathered around a real table. About the only difference is that we can't actually flip one another off or throw dice at each other now.
Now, there are some differences in gameplay - it tends to be a bit slower, and I haven't found a good way to draw a map on the fly. But for the most part, if you adjust what you do for prep, it can work really well. Make or find a few good maps, write up all your flavor text to copy and paste, keep the SRD open to any monsters or rules you need. Plus, we tend to type out most in-character stuff, so people have an easy, convenient log of what happened in the game to reference. Now, everyone in this group types fairly well, and if they didn't, we might be inclined to do the in game stuff over Skype (as opposed to using it for questions, rule clarifications, and mocking each other incessantly).
If I had a choice, I'd play face to face, but online has been a real boon for our group, at any rate.