The Sony Reader is no longer listed on Borders.com, and according to the eReader expert in my local store none of the Sony Readers can be ordered anymore.
Borders is now down to only 2 eReaders in stock, the Kobo Wifi and the Cruz Reader Android tablet. Both can access the Borders eBookstore from the device, which might explain why the rest were dropped.
But this could also be a situation where Sony might have pulled its eReaders from Borders in response to the bankruptcy. Back in 2008, Sony is reported to have suspended shipments to Circuit City. Note: the Sony Reader is still available everywhere else, so this isn’t a general retreat from the market. It would be more of a vote of no confidence.
On the other hand, Borders had already cut its eReader selection from 7 devices to 4. This could be another step to simplify its selection and reduce the hassle and overhead.