Every year, more and more advanced technology is being released every day. Sure, getting an R9 290x will help but is it worth it now? An R7 260x can run current gen games just fine. When that gets outdated, add another one or buy an R9 270x or higher. Games from now until the next generation won't see much change in performance or graphics. An R7 260x will do you fine FOR NOW.
BTW, new hardware for games won't be incredibly demanding because remember, consoles are not changeable (As with hardware) so games have to work with them too.