Ok, this is just my interpretation of course, and I may be way off track, but...
A lot of sellers have moved the 'lions share' of their Store Listings to the new 30 day 'BIN' format. Some have moved all of their store listings and have closed their stores...
In the past, I would list a few items of a specific product line as auction items to entice byers to visit my eBay Store. Now I have zero items up for Auction, and all of my items are now 'BIN', but I have implemented a 'free shipping' format to increase exposure even more...
If I interpret the graph Pierre has provided above, then in less than a week, the number of 'BIN' listings have increased from 15,600,000 to approx. 18,600,000, a difference of 3,000,000 BIN listings... (approx. 16%)
If that in fact is the case, then when a buyer searches for a specific item, then instead of getting 1,000 results he is now getting 1160 results, depending on the item of course, it could be less or more, but you get my drift...
(ie)Search on Butterfly Earrings now renders 1,480 results, yet, for example sake, before the 16th, the results might have been 1243...
I find that the 30 day 'BIN' items are interspersed with the auction items... So, a couple of my items are coming up on page 1, maybe 1 on page 2, a couple on page 3, etc... (Using the Best Match) As opposed to all coming up on page one as auction items when the time for the auction closes approaches...
Forget about 'Ending Soonest', because my 'BIN' items don't show until page 10 or 11... Depending on whether your item is unique or not of course...
So, is the new 'BIN' 30 day option going to be a blessing or a burden to powersellers??
More 'BIN' items, means more pages of items after a search is initiated by a Buyer. Best Match search criteria intersperse our 'BIN' items, and Ending Soonest search criteria puts our listing out into oblivion...
Your thoughts on my interpretation please...

"If we had no winter, the spring would not be so pleasant: if we did not sometimes taste of adversity, prosperity would not be so welcome."