One more vote for 8 points for most of my framing carpentry. I have cut 4X4s with one with no problem if the 8 point is sharp. When I was young and working for a carpenter, the 8 point was the type used by most of the carpenters around, as far as I know, for most carpentry involving framing, siding, etc. Almost everything except finish work.
For finish work I use a 12 point. Back when I worked for the carpenter, some of the guys used 10 point saws for finish work, probably it was 50/50 on the 10 points and 12 points, but don't know for sure.
Unlike Tom, we did not use much hardwoods, so I can't comment on other saws for carpentry for oak, etc. However, now I tend to use a 12 point on the hardwoods I use, because any time I am cutting hardwoods quality of the cut is the important thing, and i get smoother cuts with a sharp 10 or 12 point, although such does make for a somewhat slower cut.
That said, the main point is SHARP for good cutting action.
Regards,
Stew