PhDs can be very beneficial. They teach you how push an area forward with novel work, how to plan your own time and at the end, if your doing it right, your an expert in your field.

They aren't for everyone, but increasing numbers of game devs are taking them seriously.

One thing though - make sure the subject of the PhD is relevant to the career path you want!

G

If you are interested solely in entering the game development field, DO NOT ENTER A PHD PROGRAM. It will be a waste of your time and you will probably hate it. A PhD is a chance to do research. It won't make you a better programmer (at least, not as much as spending the equivalent amount of time programming would). It will teach you things that will be useful to you later on, but many of these things you would learn as a masters student anyway. A PhD is for someone who wants to do research. If you don't like being there, you shouldn't be there.

/me goes back to his PhD