It's worth bearing in mind that in areas of NYC where the bus is the only option, a bus commute is often much much longer than a subway commute. I had the displeasure of attempting a few bus commutes into Manhattan from my old neighborhood in Bed-Stuy, and I would not be eager to do it again.

So, while I agree that one shouldn't completely ignore the buses, I think it is also misleading to treat them as equivalent to subways.