New Mailboxes: Ok, this is really minor, but it's been something I've been hoping for since Burning Crusade. More mailboxes will be added to Stormwind, Undercity, Darnassus and Orgrimmar. Anything that saves time and gets me back to questing is a good thing.
More travel options: They are adding a zeppelin from Thunder Bluff to Orgrimmar. This is long overdue for young Tauren (and will help with It came from the Blog events). Portals from Stormwind and Orgrimmar to the Dark Portal will also be added and a flight path from there to Shattrath will be available for characters new to Outland. This will definitely save time for leveling, but I am also having a bit of a "I had to run to Stonard and then to Shattrath and it was uphill both ways" kind of reaction.
UI Changes: Blizzard has tweaked the UI in a few ways: autocomplete for names, colorizing names by class, vendor prices listed on items, quest log improvement, and more. You will also be able to see which enemy spells are interruptable. My favorite addition is the ability to alt-mouseover any item to compare it to what you are wearing in that slot.
Quest Tracker improved: I like QuestHelper, but it's a resource hog and Dalaran isn't very fond of it. Finally, WoW's in-game tracker is going to start putting quest objectives on the world map and I think that means I'll be able to uninstall QuestHelper for good. I'm not lazy, but sometimes I'm all over the map, literally, and I like to have an easy way to remember what quests I can accomplish in my immediate area and, more importantly, where I need to return them.
Itemization buffs: Wrath randomized equipment loot (of the animalname) that is green or blue will now be a lot more powerful. This is good, because right now the random drops in Northrend are a bit on the lame side. Also, all mana per 5 items will give 25% more mana.
Arcane Torrent is now an interrupt against NPCs: I know this only affects Blood Elves and the people who group with them, but I think it's worth noting (maybe because I have a few Blood Elf alts). If an NPC cannot be silenced, Arcane Torrent will act as an interrupt. I have been stubbornly trying to use it as an interrupt for some time while soloing, so I'm happy that it will actually start working as I want it to.
Mounts and Travel Forms: Mounts are going to be cheaper and available sooner and travel forms will be be available even earlier to compensate. This is huge for those of us still leveling and with tons of alts. Also, the casting times of land mounts have been reduced from 3 to 1.5 seconds. Yay speedy getaways!
Tier 9 Emblems are now available via Daily Quests: The emblem changes are more complex than that and are very controversial, but I'm going straight to the crux of the matter for those of us with limited playtime. 10 mans may be considered casual, but if you only have a couple hours to play at a time, they aren't really practical. 5 man instances, on the other hand, are doable for many. With Emblems of Triumph being awarded for completing Heroic and regular daily quests, casual players will theoretically have access to Tier 9 gear. I say theoretically, because while a short-playsession player can complete a 5 man daily quest, the overall time commitment to be able to actually collect enough Emblems to buy just one tier 9 piece is far from casual. Completing a regular daily quest every day will still take 2 months to buy one tier 9 item. And that is playing every day, something we don't necessarily do. I am very sorry if you are one of the players who feels that non-raiders should have absolutely no access to Tier 9 gear, but don't expect to see a piece of it on any of us for months after you have your full set.
Battlegrounds will be more casual friendly: I am very excited about the BG changes that are coming up. I used to love Warsong Gulch when people actually played it. When it has a 20 minute time limit and allows for ties, I'll be back with bells on. Arathi Basin and and Eye of the Storm both require fewer points to win and less time to take over flags, so those will be quicker and probably more fun. The biggest news, however, is that completing objectives (capturing flags, winning the game) will give experience. This means that if battlegrounds are your thing, you could level up completely doing nothing but PvP. Note: Killing players will still not give XP. Also, twinks can turn off XP so they won't level, but that means they will only be playing against other twinks. In other words, your level 12 in whites and maybe a green or two will no longer have to contend with ubergeared/enchanted perpetually level 19 WSG professionals.
Well, this has taken me forever to write and I'm neglecting my It came from the Blog DK. Remember that some of these changes may not make it to the actual game, but hopefully they will. What are your favorite changes that are on the way?