"With the new Sony PlayStation Store being a firmware-level process (as opposed to the glorified website of yore) some were concerned that Sony might take the chance to region lock the PlayStation Store, ending our days of Japanese downloads through the exploit of using multiple store accounts. Luckily, Sony has opted not to plug the obvious holes in their system. SCEA stated that, "no changes to the store will be made as part of this revamp relating to region locking." So consider the confirmation a small, good thing."
http://kotaku.com/375771/new-sony-store-wont-be-region-locked
This sounds good, if nothing changes, for those who have multiple accounts. I know people that go to the Japanese store to catch demo's and such.