If I’m in the market to buy jewelry, I will definitely buy at 50% off (if the seller does not move up the original price before he applies the discount). 50% off is typically the wholesaler price. The store is selling at cost. I’m happy to take the jewelry at this price. You can similarly argue that the wholesale price may also drop. But I don’t care.
I don’t know why people are arguing here. If you want to wait for the bottom of the price, this may not be the time to buy. We will know the bottom after we have passed the bottom. Since the price most likely will not be V-shape, there will be plenty of opportunity to get the bottom-like price at that time.
But buying house, like buying jewelry, like buying HDTV, may not be purely an economical activity, many of which are life-style choice. Today’s buyers will definitely not looking foolish if he can hold onto the property for a long time. As Rich pointed out in his article, the housing price has become reasonable at many places, especially the locations where price has been 50% off. Even if the price worth only 1/2 what we paid for 20 years from now (like the Japan example you gave, although I didn’t check the data to see if it is true), SO WHAT? Price is definitely much much lower than 240x rent right now. 20 years of renting would cost you MUCH MUCH more than buying, who cares if you can get another 50% off today’s price at that time. You are paying more on rents and you missed out the joy of 20 years of homeownership.