If you're really in doubt, list both. It takes about 3 seconds to type "10c to f" into Google and you have your conversion. Just *make sure* you mention *which* temperature gauge you're using - 60F is very very different to 60C. If someone elses question doesn't mention, but it's pretty obvious, then edit it in with a conversion to both F and C. Or to K as well if you really want to hammer the point home.

Really though this should go for anything where units differ between countries - for example, [voltages][1]. I received [warnings once from a user][2] who didn't realise my systems run on 240v - and why should he? I never made any mention of it in my question.


  [1]: http://serverfault.com/questions/56999/testing-a-ups-by-unplugging-it-from-the-wall#comment45549_56999
  [2]: http://serverfault.com/questions/56999/testing-a-ups-by-unplugging-it-from-the-wall#comment45544_57068