Detailing every class change is somewhat beyond the scope of this particular article because enough balance issues are addressed in patch 4.2 that it'll take some reading to get caught up. The most important note, though, is that Blizzard Lead Systems Designer Greg "Ghostcrawler" Street addressed many of the reasons for changes in a direct, informative way. It's always nice to know why things are happening, so take the time to check out his explanations.
You should take note of the changes to crowd control. Using a CC spell on an enemy NPC will no longer automatically aggro that mob to you. This is a huge quality of life change that will help PUGs and raids alike. Your repair bills (and tank) will thank you.
New recipes will be hitting the ground in patch 4.2 and a whole new raid tier is being opened. That means that tradeskills will see some heavy use in the initial weeks of patch 4.2.
With the changes to Mt. Hyjal and even the new Firelands zone, poking your head in new and exciting places will be novel again. The Encounter Journa
l will allow you to look up bosses while in the game; you won't be forced to go to a 3rd party website to look up boss abilities. Its interface even looks pretty cool
There are new little fun items being added with the new patch as well. These are (usually) things that are still amusing touches to our game play, but don't radically shift your character's power level.
The new daily quests
in patch 4.2 will probably be the biggest deal to casual and new players. Daily quests allow you to enjoy the questing experience every day. More importantly, the new quests in Mt. Hyjal will advance the story in the zone, allowing you to personally take a role in healing the burned land. Advancing your reputation by doing these quests will allow you access to some pretty cool rings
Tier 11 raids nerfed
We talked about it before, but it is worth repeating: The extant tier 11 raids will be nerfed
by about 20% in the patch. That means you'll be able to get together a relatively casual group to quickly clear those instances.
This is a big deal for people who didn't have the time to clear this content already. While the hardcore move on to Firelands, tier 11 raids will become our playground.
Visit the WoW Rookie Guide for links to everything you need to get started as a new player, from how to control your character and camera angles when you're just starting out, to learning how to tank, getting up to speed for heroics and even how to win Tol Barad.