Blair has posted the August 2013 Tool newsletter, and it discusses his recent wisdom tooth removal as well as some movement in the Loft:
The first thing that I noticed was that some of the band’s equipment had been moved back to their usual places, meaning that the guys had probably delivered the goods to MJK, and were now back in their ‘normal’ writing session mode. Then I saw further evidence on a new Dry-Erase board that was filled with indecipherable scrawls written with a red marker. Studying this the best I could, I realized that this indeed was a curveball of the likes of Feller or Blylevin. But then again, a better baseball pitch analogy might be that of a changeup such as thrown by Martinez, Verlander or Glavine.
No solid news as to what the curveball may be, however I suspect there’s a few hints in there for those who look for that kind of thing. It does however, sound very much to me like Maynard does have his hands on the new tracks as hinted in his “recent” interview, and the newsletter does appear to suggest something happening in September.