My main point is just that IMO RC in general - nitro or electric - is a hobby, and as such entails input from the owner. By "input" I mean learning, maintaining, repairing, maybe upgrading, etc..
That said, in my opinion, if this thread is ostensibly about what to get for an 8-year old, then what it's
really about is what to get for the parent who's going to have to buy, maintain, and repair it(and oversee its use..) I have both, and for me personally I prefer nitro. For a young kid, I can imagine opting for electric, but not for any reasons given so far. Mainly, because you can put the power down to like %25 and work up step by step so they can learn to handle it. But that depends on the people and what their priorities are - more to build something together, more just to drive it in the yard, or what.. With nitro, especially if the parent doesn't know how to run them, it can be more of a challenge. BUT - some people like that. Maybe the parent wants a project like that - to learn together how to run nitros, etc..
I run at a local park that has all kinds of RCs - electrics, gassers, nitros.. And lots of people stop by to watch. And in all honesty, the kids (and old people alike..) are more bug-eyed and awed at my nitros than the others... There's a 6s E-revo which is very fast (when it's not out of commission with broken axles and diffs..), but my LST2 with LRP ZR.30X is no slouch. LOTS of fun - and honestly, brushless doesn't have much on it - maybe a bit of top speed.. It also idles and tunes great..
Here's the last outing:
http://www.youtube.com/watch?v=_vSdwHqui08
Crummy jumping(overrotating the flips..
) - rusty after the winter.. But the truck stood up to it and ran and still runs great...
Anyway, IMO it's up to the parent. What do they want? To do and learn something together? To just let the kid play in the yard? Where do they plan to run the things? In the street out front, or maybe they have a cool offroad site? As with EVERYTHING, there are a ton of variables, and canned simplistic answers like "electric is easier than nitro" are of limited value.. Everybody's situation - like their tastes and preferences - are different. Take the kid to see some RC's running - nitro and electric - and let him decide..
All that said,
NITRO RULES. 