It might have seemed that way to you, but not every class had one viable build per tree. Priests for example have several viable PvE holy specs and I've seen well progressed people using all of them. I've seen lots of end-game tanks with more than one tanking spec as well.
Its the DPS classes who are most cookie cutter because the math exists to support a theoretical "max" dps spec in an ideal situation, which is what most people who care read about on elitistjerks.com and go for. I was in an ICC10 pug the other night with no replenishment buff and couldn't help but think as I chugged mana pots and watched my shadowfiend cooldown that the 4k dps marks hunter would have been more useful with a survival spec. If only he knew better.
This ^^. It fits with my theory that Blizz (not so) secretly wants us all to PvP more. I would also bet money that unlike all of you, 90% of WoW players *never* research their class on *any* website, and by condensing the talent trees, Blizz continues it's trend of catering to the masses. Whether we think this is good or bad, the bottom line seems to be that talent specs aren't going to play as important a part as they have in the past in determining a player's success in the game. It's going to boil down (as it always has) to how well you pay attention and push buttons in response. For DPS players who care about maxing their performance I see this as a win, and for tanks and healers, it really feels like a loss. But for the typical player who didn't take the time to really learn about their own class in Wrath and the previous versions of the game, it's probably a good thing no matter what spec they play.