I have a new 05 WRX with about 650 miles on it.

If I leave 1 interior maplight light on for more than about 6 hours, the battery is gone and it needs to be jumped. If I leave my parking lights on, it needs to be jumped.

Is this normal? Doesn't seem that way to me - my previous vehicles never had such a problem. Do you guys find that your Subaru has a weak battery, or do I need to hassle my dealer?

The stock battery is JUNK. This is a known issue.

Get a GOOD battery and be done with it.

I do agree with Scotty, but since you have a new 05 you should go to the dealer with it first. If the battery is shot they will give you a new one, then you can always decide to replace it later. Also I haven't looked under the hood of an 05, it's possible the OEM batteries are better now. I've seen bigger ones in newer STi's but not sure about the WRX.

Well, if its really just a cruddy battery, I will let the dealer replace it once, and if it still behaves this way, I will make them buy me a decent one.

The dealer will replace it with another OEM battery, whatever that is. They will not upgrade it for you to something else, not for free anyway. You'll have to do that on your own.
You should also have them check the car for excessive standby or "parasitic" drain, it could be this and not the battery.

You've clearly never dealt with me as a pissed off customer. You'd be surpised what I've gotten vendors and dealers to do :).

Best I ever did? Got Audi USA to buy back my mother's borderline lemon A6 and buy her a Lexus GS at wholesale - they ate the cost difference. And thats only 1 example :). Others would include getting a Sears to replace all 4 tires because they damaged one, and getting my Ford dealer to extend my warrenty by 6 months due to ongoing issues.

I don't think a battery issue will stand in my way :). I will give them a chance to make it right with a new OEM battery. If I continue to have issues, then they will be forced to deal with buying me another brand or model battery.

Well that's great if you can pull it off, I know that some people can but it also depends on the dealer. If you do, make 'em spring for an Optima.