EDIT: One last point. Probably the best way to detect a mining botnet on your computer is to mine with it. If your hash rate drops then you know something is wrong, be it hardware failure, software failure, or a botnet. There is no way for a botnet owner to steal your hash rate without reducing your hash rate.
lol nice rationalization to mine on any and every computer you ever own or have access to
In case it was not clear I find botnets reprehensible and have nothing to do with them. That is independent of understanding the economics of it.
I was just referring to your EDIT, that I left in the above quote, not implying you condone botting or netting or anything
Oh okay. Somewhere in the comments from the cryptonote folks, they describe their "one cpu, one vote" concept as including a (distant) vision that every computer, cell phone, etc. will be mining all the time. This makes the sort of botnets that exist today impossible. It also makes 51% attacks much harder since there is no idle capacity to use. For example, in this model Amazon's cloud nodes would just mine for Amazon when no one else is renting them. It also implies a change in the design of CPUs away from power scaling and efficiency at idle to efficiency at full load.
Of course this is not happening in full form any time soon. We may move in that direction though.