The PC is a far more flexible tool. If all the PC could do was play games and media, you could compare them, but that is not the case. You can't compare the two directly based on price, because they do not have the same capabilities.
Read local/world news
Make voice calls
Browse internet - youtube/justin tv (being able to take advantage of any format).
A lot of the time I'm doing several of these things at the same. So even if PC's are more expensive I'm using it for more purposes than I would console . Well worth it.