I don't get it. I mean, we've all known for quite a while that mobile counterparts (of anything, for that matter) would always be slightly (or sometimes DRAMATICALLY) lower in performance than their PC counterparts. I mean, compare the size of the two for God's sakes! It's like saying that HEY! My headphones aren't half as loud as my Hi-Fi - (Well dumb-o, note the difference in the 40mm drivers vs. the 250mm ones in your boombox?). It's like saying that my BIKE runs way, WAY slower than my CAR. Yeah, it's 600CCs, but I wanted it to be 2400CCs (same as my car) and hold 4 people, too.
I mean, come on! A laptop is only about twice the weight of a top of the line and flagship AMD or Nvidia GPU! The heatsinks and the card lengths! All that for some showoff? Well, n00bs would think so...
I like where this article is going, but most of us already know all that. I mean, the naming scheme is just so to identify that if the 580 is the best Nvidia chipset in the single-GPU based DESKTOP solutions, so that 580M is the best single-GPU in MOBILE solutions. Simple. Like we say that Dr. Dre beats are the Ferrari of Headphones. So, if Ferrari was into making headphones, Beat Studio would be what they'd be making. So you can surely call them the Enzo(s) of headphones, but you can sure as hell not ride in them, let alone at 200MPH.
Bottom-line: Where's the Confusion?