The PS3 and Vita storefronts might not be closing for the foreseeable future, but Sony is about to make purchasing titles on these platforms a little more arduous. The console manufacturer has just updated its support page with a notice detailing that from October 27 you will no longer be able to purchase titles using PayPal or your credit or debit card.
If you're still wanting to purchase titles on these system then there is still a workaround. You can still use funds from PlayStation gift cards and you can add money to your wallet still by accessing the PlayStation Store via a web browser. Obviously, though, this is an inconvenient change and it could just be the start of Sony rolling back support for these older platforms.