The stores who are converting to that format are selling all non-bestseller / new release cds and dvds at 50% off, but they're not promoting this fact, except on in-store signage!
While doing errands, I wandered into one such store and, upon seeing the sale signs, immediately headed for the media section, hoping to find TorchWood or Dr Who dvd box sets (They're the only series I haven't been able to find at reasonable discounts) or old radio show cd sets.
I didn't find any of the above, but what I did find was...
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It now sits on one of my media library shelves next to my James Bond, Flint and Prisoner box sets. ;-)
You might want to check out Borders near you for similar sales...