New Talent Pane
One of the biggest changes is of course the new talent pane. With the talent system being revamped to 31-point trees, Blizzard has taken the opportunity to design a new, more intuitive interface to introduce players to each specialization they have available to them.
The glyph system is getting an overhaul in Cataclysm as well, so to go along with that the glyph pane has been updated to reflect the changes. Using a glyph will now "teach" your character that glyph -- permanently making it accessible via the glyph pane as an option to add to your active glyphs. All of the glyphs you've learned, and those still available to your character, will display to the right of your active glyph section in a list that is easy to browse. In the screenshots you'll notice that glyphs you do not currently know will be greyed out.
In addition to this, ability icons on your hotbar will now light up with a glow effect when they become available for use, or when one of the spell overlay effects are active that the ability will benefit from. For example, check out how Howling Blast and Icy Touch look on the action bar while the Freezing Fog buff is active.
The default raid frame UI has seen substantial improvements and will be much more viable to use over an AddOn in Cataclysm. As you can see in the screenshots below, it can be customized quite a bit and is visually similar to the popular Grid AddOn.
To go along with this, the UI options for the raid frames have been updated.
Spellbook Update - Mounts & Companions
The spellbook has been updated with new tabs for your mounts and companion pets, so they no longer display on your character pane. The nice thing about this change is that the spellbook now displays not only the icon but also the name of your mounts and companion pets -- making it much easier to browse and select the right one for the situation.
Character Pane - Expertise and Hit Chance Explanations
The character pane has received an additional update for the Expertise and Hit Chance statistics. You'll now see detailed information on the chance for your attacks to be dodged, parried and miss based on the level of the creature. This will greatly assist players in choosing gear upgrades and what gems or reforging to take advantage of.
Character Pane - Spec and Class Color
The character pane has also been updated and will now display the spec you've chosen alongside your level, and it will also be colored in your class color. It will also display on the inspect pane, making it easy to quickly see a person's chosen specialization.
Reforging is a new feature in Cataclysm that allows you to reduce a secondary statistic and put those points into another secondary statistic, by visiting a Thaumaturge NPC. This system allows for incredibly customizable items and lets you tailor them to your specific needs.
And as a reminder, I've included a video introduction of the reforging system.
Druids will find when they choose the Balance specialization that they have a new mechanic bar: Eclipse energy. Using certain spells will generate either Lunar or Solar energy, and once you reach 100 it will proc an eclipse of that type. Lunar will increase Arcane damage, while Solar will increase Nature damage.
Hunter - New Pet Pane
With Cataclysm, Hunters will be able to have multiple "active" pets -- up to 5 at higher levels -- and they can call upon any of them while out questing, doing dungeons, etc. In addition to this, you'll also be able to have up to 20 pets stabled. This called for a new pet pane, and what you see below is the result.
Mage - Portal & Teleport Bars
Mages now have a new feature for their portal and teleport spells. Rather than each spell being displayed in the spellbook, there are now two spells named "Portal" and "Teleport." Upon clicking either of them, a bar pops out that allows you to select which destination you'd like to port to. These spells can also be moved to your action bar, resulting in similar pop-out functionality.
Paladin - Holy Power Bar
With Cataclysm, Paladins are going to have a new resource system. While they're retaining mana as a primary resource, Holy Power will be used exclusively for a handful of abilities that grow in power based on the amount of Holy Power you currently have. To support this new resource system, a new UI element has been added for Paladin players under their unitframe. As you see in the screenshot examples below, as you have more Holy Power, the bar glows more impressively.
Minimap Update - Quest Tracker Arrow
The minimap now has an arrow pointing to your primary tracked quest, assuming you're using the quest tracker feature. It was updated recently and now looks much better.
Thats all for this post stay tuned for more Beta updates!