Bracken's a fine ODI bowler - in fact, he's well on the way to being a genuinely great ODI bowler. Not sure he'll get much of a go in tests in the near future though. Clark, Lee and MacGill are certainties next summer, as is Watson fitness permitting, and I think the temptation will be to go for an unproven bowler with the potential to be devastating to fill the other spot, like Johnson or Tait or perhaps Hilfenhaus, rather than a safe option like Bracken. I think Bracken could probably be a good test bowler, but the assets which make him so good in ODIs wouldn't really have an impact in tests, particularly if he's not given the new ball. 120 kph cutters aren't going to frighten too many set batsmen in a test.
He could be extremely good if the ball is swinging though, or in the subcontinent. I'd not mind seeing him get another go at some point, but I just can't see it happening next summer without a string of injuries.