The new talent system may seem daunting at first glance. But it's really not as complicated as all that. Let's cover what is and isn't changed.
For starters, while you no longer have to train abilities as you level, your class trainers do still provide several services related to talents. For a fee, your class trainers can completely reset your talents, allowing you to pick again from every talent tier you have available. They can also completely reset your glyph selection, allowing you to reselect your glyphs, and they still offer Dual Talent Specialization for 10g. They also allow you to reset each of your class specializations. The various reset services cost you gold up to what appears to be a cap of 59g, although that may change before the game goes live.
If you wish to reset a talent of glyph manually and individually rather than resetting all of your talents and glyphs at once, you'll need Tomes of the Clear Mind, crafted by inscription. For the purpose of patch 5.0.4, you won't need to worry about these, since they only work for level 86 characters. Until those are in the game, you'll be resetting your talents and glyphs at the trainers only.
As for the system itself, it's actually very simple. Every 15 levels, you gain access to a talent tier. This tier consists of three talents, and you get to choose between the three. So using the shaman talents above, at level 15 you can choose between Nature's Guardian, Stone Bulwark Totem, and Astral Shift. Once you make this choice, you're done with this tier of talents unless you decide to change your mind. You can't, as an example, spend the talent point you get at level 30 on a talent on the level 15 tier, nor can you save that talent point to spend at level 45 on the level 45 tier talents. Each talent point you get is specific to the tier for that level, and you can never have more than one talent per tier.
One talent per tier, no exceptions
So when patch 5.0.4 drops next week, you will have five talent points if you are above level 75, which includes all level 85 characters. You can spend these points immediately at the level 15, 30, 45, 60 and 75 tiers, picking one of the three talents available at each tier. Each class has its specific focuses per each talent tier. Using death knights as an example, the level 60 tier gives you three different talents each dedicated to self-healing the death knight in a specific way. It's usually readily apparent what each individual tier specializes in per class, and the talents are designed with an eye toward personal preference, although different class specializations might favor one over another.
That's the new talent system in a nutshell. Until Mists of Pandaria goes live, we respec our talents, reset our glyphs, and choose class specializations through the trainers as we've always done, and we have five talent points to spend at level 85 in five of the six tiers, the sixth being the level 90 tier and thus inaccessible until Mists itself. Now get that tuxedo off of your parakeet until it's time for the bird prom.
It's open warfare between Alliance and Horde in Mists of Pandaria, World of Warcraft's next expansion. Jump into five new levels with new talents and class mechanics, try the new monk class, and create a pandaren character to ally with either Horde or Alliance. Look for expansion basics in our Mists FAQ, or dig into our spring press event coverage for more details!