Electric Powered R/C Aircraft  vs.     Gas Powered (IC) R/C Aircraft
ADVANTAGE ELECTRIC:
ADVANTAGE GAS:
10) Massive selection growing everyday
9) Kits are getting Extremely Fast
8) Kits are Extremely Light
7) Foamies!!! Very Durable
6) Dont need a Flight box anymore
5) All you need to for routine flight is a charger
4) EDF power!!! is available at almost the same price as a prop.
3) Only have to buy one Radio
2) Extremely quiet

And the Number one reason for ditching Gas...

1) I Can Fly it Just about Anywhere
10) More power in the engine so weight doesn't matter
9) Lots of Kits around
8) Lots more used/prebuilt for sale (cause everyones going to electric..hehehe)
7) Flight times are longer
8) Can go all day with out a recharge
7) Only have to buy one radio
6) ...

Well thats all I can think of..
.
Intial cost to start is about the same however you slice it. I think that was on purpose though, so you may see some cut throating in the future as the market develops.