doubtful that it blows away the desktop 980. pound for pound, desktop is always better.
Of course it's slower than the desktop 980, but it is faster than most desktop cards out there, and it's available in some pretty amazing laptops. P35x v3 is starting at $2100 and only 0.8 inches thick, cheaper than the Razer Blade.
Also, it has 8GB VRAM, so it meets Shadow of Mordor recommended specs to use the Ultra texture pack with downsampling. The desktop 980 cards currently on the market have only 4GB VRAM and are below specs for this game. Even if you have a beastly desktop with four GTX 980's in SLI, the frame buffer is mirrored and you are still stuck with only 4GB VRAM.