and if you wanted to run for more than 5 minutes, nitro was your only choice.
5 mins is exaggerated.
It also doesnt matter, this isnt a few years ago, this is now. And batteries are clearly the way to go.
what's the typical cost to get into this hobby?
Depends on what you want to do. Street race, off road, what scale, what type of batteries you want. The most popular is SCT. Short course trucks. Such as the one linked above. They can take a ton of abuse, and with the right batteries, can go upwards of 60mph. You can lower the suspension and race on the road, with road tires. Or put dirt tires on, and race a dirt track.
Be warned, if you decide to dabble, you will get sucked in. You'll want this, then that, etc.
Here is a video of my E revo doing a flip last week. Nothing fancy. Was out of town for a friends wedding and brought my toys along. Found some wood, and a cinder block to make a ramp. You can control the vehicle in the air. Give it throttle and it will bring the nose up, brake and it will send the nose down. This was about 1/3 speed. I cannot punch the throttle or it will come up on the back wheels unless Im already going 40mph or more. Wayyyy too much power.
I didnt edit, sorry.
http://www.youtube.com/watch?v=xTigH9O5aWI