from the reading I have done and People I have talked to I have gathered that the dogs ribs shouldn't be visable but you should be able to feel them with your hand.

Remind your wife that he is young and is growing up right now and after about a year will start to broaden out and little bit. Also Such dogs are built lean and long a little bit like a grey hound. That coupled with the short hair make the dog look skinny. I would compare him to other dogs of the same or simulare breeds.