As for Bart, he's retired because the Speed Force is gone and he no longer has super-speed. Joan Hilty said something like the SF would be more important than ever in the post-OYL DCU, though. My guess is that it'll come back in some new form and Bart will come back as the Flash. Or, at least I'm hoping that'll be the case. While I'd prefer Jay Garrick as the Flash rather than Bart, I certainly don't want to see the Flash stuck at the speed of sound, max, because he's just got meta-gene-based speed. The whole Crisis has just sucked for the Flashes all around, it seems.