Is Now the Time to Buy?

I have an arguably over-simplified view of the housing market; I believe it looks like the graph on the left. This graph represents my "gut feel" approach to deciding whether or not to buy a house.

I believe that typically, housing prices follow a mostly linear upward path (indicated by the black line). However, the recent economic fiasco as caused the geometric deviation illustrated by the red curve.

If you already owned property, the best time to sell would have been point A. Clearly, we are already past that. If you plan on buying, any time after point B is the best time, with point C being the best. So the question is: where are we on the curve? Have we even passed point B yet?

I honestly don't know; in fact, nobody knows. Of course, a lot of people think they know, but only time will tell. My hunch, based solely on the "feel" of things, is that we are a bit past point B. I asked my dad about this, and he thinks we haven't even passed B yet. But both of us are basically just guessing.

Anyway, I'd like to hear the comments and ideas people have regarding our position on the curve. My wife and I are loosely thinking about buying... is now a good time?

Side note: I made that graph with a nifty little program called xfig.