So I'm thinking of going overseas in Nov/Dec this year which has me thinking if the 3DS' supposedly poor battery life will be enough for long plane/train rides (4-8hours). Even so, I think it's unlikely they'll release a new model with improved battery life before the end of this year... 
 
Apart from the overseas trip, I'll mainly be using it at home where battery life will be a non-issue. 
Should I just buy one now and deal with the poor battery life overseas? Or wait it out until a second model is announced and make decision then? 

If you'll be at home most of the time, battery life shouldn't be an issue. For long rides you can disable unnecessary features, turn down the brightness, whatever. Battery life can vary.

If you are bargain hunter, you should get a psp or a ds. Their prices are hitting the lowest point, and their games are almost given away. :p 
 
If you're a tech aficionado, get a 3Ds, but with the current games, you'd probably be better saving the money. You should wait.

" If you'll be at home most of the time, battery life shouldn't be an issue. For long rides you can disable unnecessary features, turn down the brightness, whatever. Battery life can vary. "

" If you will be at home most of the time, you shoudn't need a portable so expensive as this one "

I've already got a DS and have been hanging out for the 3DS for a little while now. I might take @LordAndrew's advice and get one now.
Surely better first party games will come out in the "launch window" so I'll just hang out for them.

I haven't owned a nintendo handheld in a very long time, i'll be buying a 3DS as soon as a game I am interested in is about to be released on the platform. 
 
None of the launch titles interest me even a little.