Barry Allen is back because Geoff Johns likes him better than Wally West. We could swallow it because Wally suddenly had twins he had to raise, so at least he had stuff to do. With the impending DC reboot and the New 52, featuring Barry Allen as the Flash and Bart Allen as Kid Flash, Wally West is going to be joining the Justice Society of America as concepts that DC is "resting." Which means until someone comes up with an exciting pitch for him, it will be as though Wally West was never the Flash, despite spending decades in the role as many fans' favorite Flash.
So, if you want to see Wally West as the Flash again, you'll either just have to reread all the old stories, or check out the DC Retroactive line, as the 80s and 90s versions of The Flash should show off Wallace Rudolph West in all his glory.
This Wedensday, you can get DC Retroactive 1980s: The Flash from writer William Messner-Loebs and artist Greg Larocque, and watch Wally back in action and dealing with Captain Cold and an obsessive fan. Check it out.