Price drop and memory card in the box will help a little, but it will never fully rebound. Sony dropped all kinds of balls with the Vita, no memory included being the most egregious omission. They got away with that during the PSP days, but it's a different world out there now, and people expect to be able to use their shiny new toys when they unpack them instead of having to immediately drive back to the store.
The second ball-dropping is that their release strategy seems to have been:
1. Release Vita.
2. Stop talking about it.
They don't appear to have any real confidence in their product, and it shows. Their big chance to make a post-release media push for their new system was their E3 conference, where all the mainstream news was watching, and Sony didn't seem to think the Vita ranked more than 5 minutes to itself. And when it was mentioned a couple of times elsewhere it was shown as an accessory to the PS3.
They won't bounce back much, no matter what they do. Every month that goes by in the real world is like six months in the tech world, and all kinds of new hotness is being announced. It's already old news, the only time it gets mentioned at all is in reference to how poorly it's selling. Vita has the smell of failure or also-ran about it now, and there's really nothing that can change that perception once it's out there. Too bad, it's an awesome piece of hardware.