I have talked to several hardwood floor specialists and there seems to be disagreement as to whether you should wax or urethane them. I was told by one that they never wax, only urethane -- but they can't urethane over existing wax so they'd have to sand and refinish first -- costing about $3000. Wax costs a fraction of that.
I personally do not care for the high gloss, coated look of urethane. Are they out to snooker me? If I get a dog will I want urethane in the event of accidents?
The main reason I'm considering refinishing the whole house is that a portion of the house has to be refinished regardless of this issue -- so ultimately I'd like to see it done right (but on a tight budget).