Like the current talent system, players will choose their specialization at level 10. This specialization chooses what abilities you'll be gaining as you'll level up, rather than there being baseline talents. There will be a few baseline class abilities, but not nearly as many. According to Ghostcrawler, these spec abilities will be "anything your spec requires." Spec abilities will be learned out in the field when you level; you only need to visit the trainer to choose a new specialization! In the preview at Blizzcon, the holy specialization for paladins received staple holy abilities, such as Holy Shock, Holy Light, and Beacon of Light. Some specialization abilities will be available to two specs, such as both ret and prot getting Hammer of the Righteous.
The other part of the talent system is that there is now one talent tree for every class. At every 15 levels, you get one talent point, which can be put into one of three talents for that level. You can't go back and take previous talents. These talents are looking to be abilities, not boring things like passive healing or damage buttons. There are no ranks for these talents. The goal is for there to be no mandatory talents, and that you should choose what you want on a per fight/per content/per choice basis. Retalenting should be as accessible as reglyphing is right now.
So, for example, a paladin will choose holy for her spec, and as she levels up will gain all her core holy abilities. When she hits level 15, she will gain her first talent point, which will be usable on either Speed of Light, Long Arm of the Law, or Pursuit of Justice, which all sound like a speed boost to me. Once she makes this change, she won't be allowed to choose the other two talents when she gets her next talent point, though she can later choose to retalent if she feels she chose poorly.
The three choices you have to take at any level will all share a same theme in common. In the previous paragraph, you have three talents that will be mobility based. (Warriors also get mobility talents at 15, their choices being Juggernaght, Warbringer, and Double Time.) The idea is that you don't forego a mobility ability for a dps ability, or a cc for a survivability cooldown.
An important point to note is that even though these abilities have the same names as current talents in the game, they will not have the same effect. They are being redesigned to try to appeal to all three specs in a talent. The point of new talents is to offer a form of utility that you can customize for your playstyle, and not mandatory choices for maximum DPS/HPS/Survivability.
All in all, it's looking to be a simplified, better, and ultimately more choice-driven take on talenting, and I couldn't be more excited.
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