I'm not convinced that the market has collapsed: but it has changed over the past few years, certainly. There have been some strong prices recently at auction for top quality paperweights, whilst the more mundane ones have floundered. I think the internet has helped people understand the market better: they realise that there are, for example, many Baccarat pansies out there but few Baccarat multiflower bouquets; or many St Louis nosegays but few carpet grounds. I recognise that this was known in the past to the trade and to the more experienced collectors, but I think that many more buyers now know it too. It is when a couple of uninformed buyers are after the same item that we see the freakish results.
I'm sure that there are many interacting factors that affect the market, include the 'unknowns we don't know about' (a bit like climate change....). Earlier commentators must be right in identifying the weakness of the US $. To that you can add the weak economy in Japan, annual cyclic effects, perhaps some residual effect of eBay (though I suspect that has been around long enough now for the initial shock waves to have subsided), the fickleness of collectors and the antiques market in general, and no doubt many more factors. But on the positive side, the weak $ makes it attractive for Europeans to buy from the USA; and maybe more important in the longer term, will we see the entry of wealthy Chinese collectors? That could really change things.
I'm not convinced by the argument that 30 day auctions would be beneficial, and help even out variations (even if that were a good thing - do we really want to establish a standard rate, irrespective of supply and demand? It sounds rather totalitarian to me.) As had been discussed in other threads, most bids are made near the end of the auction - and most people only look at the auction in the last few days, if how the numbers of watchers changes is any indication. If you carry out a thorough search for paperweights on eBay you get around 10,000: that is already far too many to examine regularly. From my perspective, having 4 times as much would not represent greater choice, but greater chaff to sort through to find the odd one worth watching.