First time I run it, I smelled something burning, so I quickly turn it off.
magic lantern CAN NOT cause anything like this.
when recording without ML, the camera uses 60% of the CPU processing power *plus* the hardware unit for MPEG encoding.
even when ML would consume 100% CPU power all the time, there is nothing that can happen within just a few minutes or hours.
also about "consuming power" and "battery getting hot" we already ran a test on two identical 7D bodies before releasing the alpha. (thanks jphansen)
both cameras next to each other with fully charged batteries. one camera running ML, one without.
after 10 minutes recording, the ML camera drained just one percent (!) more energy than the other one.
that 1% is just logical when you run smth like focus peaking.