IGN, the new PSP which is launching in September, will be getting a 1Seg TV tuner module that attaches to the the USB port on the top of the console.
There are two problems with this though, first of all owners of the old PSP won't be able to use it, as it doesn't fit, which means that the current install base is getting screwed over.
Secondly, as this is a 1Seg tuner, it won't work outside of Japan, so fingers crossed that Sony is working on a DVB-T, DVB-H or T-DMB tuner, although DVB-T is the only well established standard, so that would be the one to really hope for.
It looks like a neat accessory, although it requires that you have a memory stick in the PSP for the software, or it won't work. It should retail for about €41.50 which seems quite reasonable.