The Jaguar cores were meant to be used in laptops. In a desktop they would perform considerably worse compared to other options.
I think the big reason for the performance of the PS4 graphics being so high is that, I think they are based on the next version of AMD graphics, not the 7000 series. Also the whole system runs on 8GB GDDR5, which is crazy fast compared to DDR3 found in PC's. The Xbox one will probably have much lower performance in general because they are still using DDR3 instead of GDDR5. The way the RAM is worked into the system is probably the biggest reason for the PS4 performing so well in gaming, as the RAM for an APU in the system is a big factor holding back performance.
As for the PC APUs, they have pretty good performance in gaming really. They can run any modern game fine. They won't hit high settings on everything, but for a lot of games medium settings is well within reach. Given this is coming off an integrated system thats really impressive. The next series of APU's with the Steamroller core are expected to be better CPU's in general, have the next series of AMD graphics, and its rumored they may be able to use DDR5 system RAM. If that happens they will be extremely powerful for an integrated system.