Wheel bust after 10 months, is this normal / usually covered by warranty?
1) It's hard to say what's normal - what sort of riding have you been doing on it, as in, have you been going over a lot of curbs and potholes? The more you bounce on it, the more strain it'll have.  Have you hit one particular pothole hard recently?  How heavy are you? The heavier you are, the more likely you are to damage the wheel.

2) You should take it to your LBS, they'll be able to tell you the answer to this, but most likely they'll be able to repair it and re-true the wheel.

3) Depends on who you got it from.. and what warrantee you have I guess.  Probably going to be a general wear though I'd suspect.