I´ve to agree with D L X. The A332 is much larger. Considering the A330 order which US placed they have 10 A333 on firm order and 20 options left. These are convertible into A330-200 and A340-300 orders. Taking a look into my magic crystal ball I guess they are convertible into A330-100 orders, too. As I think Airbus will go ahead with this program this year, most probably launch it in Farnborough this year, I think that US might be a launch customer although it isn´t really likely. I see them in about 10 year from now with a huge fleet of A330-100/-200/-300 and probably some A340s.
The regional plane orders page