Boston is a big metropolitan area - sort of like London. It kind of depends on where your wife will be working and what options you prefer for commuting. (How close do you want to be to the city? And do you want to hold out for public transport?)

With the current real estate situation in the US, I'd take full advantage of that 3 to 6 months to scout out the area and see what housing prices are doing once you get there. Depends a bit on where exactly your wife will be working and what sorts of facilities you want where you'll be living.

Housing is expensive in the Boston area - but there are lots of indications that prices are coming down lately. You can read the Boston Globe online Boston.com and can even start looking through the real estate adverts. Take a look at the regional sections to get a feel for some of the suburban areas.