Been here in Japan for almost nine years, plan on staying for another three years or so. Sorry can't really tell you too much about the job market since I'm an American serving in the military. Be carefull of Nova though, quite a few guys I know who got out of the military worked for them and hated it. From what they told me they make you work crazy hours and the pay really wasn't that good in the end.
I love it here, my wife(she's Japanese) says I've become "Japanized" It's a shame I'll have to leave, if I could have it my way I'd stay here for ten more years The thought of saying goodbye to the 25t really bothers me, not even sure what the hell I would get in the states, I guess either a WRX or a Lancer EVO.
As far as cost of living whereever you go to live will make the biggest difference. The Tokyo area is very expensive, I myself live in Yokohama right now and my 1 year old three bedroom western style house is running me 169,000 Yen a month for rent. While I was living in Misawa(in northern Japan near Aomori) I could get pretty much the same house with a garage for about half the price.
What other kind of info are you looking for?