There is a profound difference between a PVR and TiVo that causes the sort of fanaticism you see in this thread and any other talking about the technology. It's functionality is simply far above what the others offer.

Anyone interested in buying a TiVo right now, though, may want to read this:
http://episteme.arstechnica.com/eve/ubb.x?a=tpc&s=50009562&f=67909965&m=59600423118