I don't think so, depends on the CPU model. Also how good and which heatsink you use.
My i7 doesn't run that hot as it 'manages' the cores and even the CPU speed. Also, my desktop has variable speed fans. When most of the cores are running up near the top and the Turbo kicks in, the computer can be confused with a HAIR DRYER!
That said, I mostly run near or below 10% CPU usage from all cores.
Cores by the way are really something that the OS has to manage, and in some cases, applications are developed that will take advantage of them as well.
My thought is the more cores the better... the faster the better... the larger the cache the better...
It really comes down to 'the future'. I don't mean tomorrow either, I mean a few years from now... your needs might change and the OS might change and just need more horsepower. Buy it now and you could put off a new purchase later for a year or more.
Are you looking to upgrade or buy a new system? W8 centric? Touch screen?
Rick's links didn't work for me, so I can't tell what the CPU temps are to be, but again, it will vary by core, cache, usage, and the heat sink as well as air flow, which would be better on a desktop than a laptop.