There's a huge difference in temps from the desktop world and the laptop world (what we are dealing with here). Smaller, tighter packages obviously produce significantly more heat. The devices are designed this way, as no one wants to hook up a garden hose to their laptop or tablet for water cooling , nor do they want to have a chassis 3X as thick with extra fans.I disagree a little. Yes chips are designed to be 'able' to run that hot but there is a reason that air and the water cooling in laptops and desktop PCs respectively has been standard for so long. I have a I5-3570k and if that ever hit 80degrees under load I'd be a tad worried.
Plus Haswell is designed to be more energy efficient due to lower voltage so this temperature is doubly worrying.
I built desktops exclusively for years, and mobile temps are simply not comparable in this regard; with mobile products such as the SP2 and laptops in general, temps are designed to run much hotter.
For example, my GT60 "gaming" laptop with the latest 780m GPU is designed by MSI to run the GPU & CPU well into 90's C. While that's a bit hotter than I like so I therefore force fans to run early to keep temps in the 70-80's C, the temps the SP2 encounters are nothing to be concerned about and are totally in line and actually a bit cooler than other comparable CPU's in full blown laptops. I'm quite frankly as a dedicated mobile gamer impressed with it only running at 80C.