After reading most of the responses so far I only saw ONE person mention the heating coil popping on an electric! My dad is a firefighter and went to dryer fires all the time, gas and electric alike! It doesn't matter if it is gas or electric DO NOT USE PLASTIC FLEXIBLE DUCTING! Avoid aluminum flexible ducting as well! Only use solid steel or aluminum ducting with as short a run as possible with as few turns as possible and CLEAN REGULARLY! My mom had the same weird fear as most people do; gas dryers are less safe than electric ones because of the lint and the flame. TOTAL BS! If you use solid ducting, SEAL IT UP WITH ALUMINUM TAPE (NOT PLASTIC DUCT TAPE), and inspect/clean the dryer and ducts often (at least twice a year) you will not have a problem.
Now, for my preference, having had both, gas baby! Why? Ever have to replace an electric element? If you're lucky you will have a Whirlpool that has the pod under the drum, if you're unlucky you'll have a GE that has the coils on the back of the drum! Either way, you have to stretch the coil as evenly as possible to avoid hot spots. BTW, if you use sneakers or tennis balls to "help" dry items you are causing extra vibration that will shorten the life of your electric coil. There is no coil in a gas dryer to break. Sure there is the gas valve and an igniter that might have to be replaced, but you probably won't have to remove the drum to do it (nods to GE dryer). The thermostats are the same. BTW the electric element isn't feathered up and feathered down while the dry cycle happens. The coil is on, or it's off, just like gas. High heat, medium heat, low heat, no heat is still controlled by the same switch on the control panel. The thermostat controls how hot the air gets. The coil might not get as hot on low as it does on high, but the flame might be as high on low as it is on high. Same gas valves do have multiple flow settings. So gas or electric? All other things being equal (aside from cost to purchase and cost to operate) gas gets my vote for ease of servicing.