Bale has already stated he'd be willing under the right conditions. That right there offers up a possibility. If the demand is there and the right story presents itself then it could conceivably happen. In Hollywood "never" only counts until someone changes their mind.
I personally don't demand there be a followup to effectively make a quadrilogy (although assuming it was good it would make for a sick accomplishment to have four solid consecutive films in one franchise). I would like to see a Catwoman standalone or tie-in with Anne Hathaway. But if there's a solid story to be told then why the hell not? After all the comics are full of stories that end dramatically and somewhat definitively only to be followed up by a new story. Same with Batman in the DCAU features.
If there isn't a fourth film then we'll get a relaunch sooner. My concern then is what form it would take. If it's a lukewarm reboot like The Amazing Spider-Man
then I could very well pass.