I've read so many disputing claims about heat damaging things, especially hard drives, vs. the Google articles that say hotter actually isn't a bad thing in reality, and so on... all the way to "bumping up fan speeds kills the fans faster and sucks dust/smoke/moisture/etc. into the computer". Personally, I believe Apple is fully aware of the temps these things get to. I am 100% certain they test them to levels in conditions that the normal user would NEVER get to, and if the normal user did, then they are, in fact the problem. Under normal use, the hottest mine EVER gets, even with rendering/video encoding/gaming... is about 75 degrees C at the power supply (on the iMac) The HDD never exceeds 59 degrees, even under the highest workload I've put it through, which was about 7 hours of pretty large transfers. It idles at about 54-56.
When I first got it, I was paranoid about the heat. I researched this for weeks, constantly using SMC fan control to maintain the temps I thought were best. But after reading TONS of pages of info, I finally decided that (personally I feel) Apple knows what they are doing, I have Applecare anyway, so I uninstalled Fan control, and reset the SMC. It never gets too hot, and I'm 100% confident it will still be kicking years from now. The fan speeds change on their own, and I've noticed it ALWAYS keeps the temps within 5 degrees of a certain level. I am sure they set it that way for a reason. But only you can decide if you feel like you can trust them, or if you feel better cooling it down. There's nothing wrong with either side, in my opinion. I'm no engineer of any kind, but I feel fine and safe letting the computer operate as designed. We'll see how I feel after using the new MBP a bit now