I received a refurb Mini 9 from Dell last week (2GB RAM, 64 GB STEC
SSD, no bluetooth) and I am finding warmer than I would have expected. It's running OS X 10.5.7 (very well) and it doesn't get burning hot — CoolBook reports temperatures in the mid 50s, celsius — but the touchpad and palmrest are often hot.
Again, not burning hot, but I find it unpleasant for the touchpad and palmrest to be hot, or even very warm. The underside also gets hot, but you don't need to keep your fingers on the bottom.
There seems to be a lot of mixed comment on this general issue, with some saying their systems are usually cool to the touch. Has anyone made any sense of this?