I'd say that many prices are slumping whenever supply ramps up relative to demand. An example was the Hetchins Magnum Bonum that sold on ebay this evening - a prime example (OK, paint looks too new) of a wonderfully crafted frame in an extremely desirable size that fetched a very modest price ($1,200 or something). The kicker is that our British friends are finding a steady supply of wonderful bikes and frames that is keeping the market somewhat supplied. Take the Carlton International that sold on ebay for just a few hundred dollars a few weeks ago. That was a steal!
The Caminargent that Ken Denny sold last week also went for a very modest price given its rarity. But, there is virtually no supply and and very little demand following it.
The Colnago that sold looked like a very nice frame. I'm not a huge Colnago fan, but truth be told, from this period they are wonderfully crafted. I once saw one of this period with American paint and the frame was absolutely stunning - it rivaled most American frames for crispness of brazing and filing (If only Colnago would fit the tubes in the bb shell better - may not really matter but it always bothered me). There is a large following for Colnago so they are usually a especially easy sell.
Now, what is tanking is the price of many Campy NR/SR items that are in good supply. Front deraillieurs are selling for a fraction of what they once were.
And the French stuff? That Rene Herse that sold for 12K shows where the top dollar demand really is - Japan.
Mike Kone in Boulder CO