Looks like the new build is here: 12479
While the 308MB patch gets itself installed, I'm reading around to see what new. So it sounds like the new talent system is in place, as expected. However, it's stated that Druids are not as far along in iteration as other classes and specs.
"While this is a first pass on all of the talent trees, death knight, druid, paladin, warlock, Arcane mage, and Assassination rogue trees are not as far along as other specializations." - GC
I'll update what I can over the day. It's bad timing, though, that I'm heading away tomorrow on holidays until Monday, so I won't be able to get stuck into Deepholme (lvl82-83 zone, which has just been declared ready for testing).
I'm liking the look of the Demonology talents, however, I feel that most specs appear not to have as much variety as I was expecting. I hope that more new talents just squeeze their way in as time goes by. I'm thinking I'll be leveling my Warlock next, so that'll get underway sometime mid-next week. I'll have a better look at Balance Druids once I've finished patching.