Thats what Japanese researchers for Sharp and Sony are saying we can expect......in 2010. The good news is that once broadcasters switch to DTV, building devices capable of recording whats being broadcast on every channel, all of the time will become much less complicated, the bad news is that even with new compression technologies like MPEG-4, you'll still need a 2-3TB HDD to store all the high definition content being broadcast, and there isn't an affordable 3 TB storage method yet, but they expect there will be in the next few years.
Another challenge is building a suitable GUI for such a product, navigating through 7,000 recorded programs could be a bit difficult. Additionally, if IPTV and video on demand services really take off, there might not be a need for all-channel recorders by the time they become available, or broadcasters might move to block them to protect their advertising revenue. Despite all the potential challenges, it is an interesting concept, I just can't wait until 7,000 high definition programs are broadcast every week.