Originally Posted by
Heladane
The optimal path seems to be:
20-58
Sequentially quest the zones (as Alliance) Loch Modan, Westfall, Redridge, Darkshore and Bloodmyst Isle - These are all "starter" questing zones with tightly packed together easy quests which have you generally doing very little for quest completion.
At the same time you should exclusively queue for Ragefire Chasm and Stormwind Stockades. These are two of the quickest completed dungeons and the completion xp alone is a solid addition to your leveling. If you are a leveling healer or tanking class this will be a sizable portion of your leveling, and you'll be getting to know these two instances well.
58-73
Do either Northrend or Burning Crusade questing while queuing for both Utgarde Keep, Ramparts and Blood Furnace.
74-81
This is the rocket fuel segment of your leveling. Switch your settings to do heroic dungeons, and go and sequentially solo every single Burning Crusade Heroic Dungeon. They give outstanding xp/gold and you will be one-shotting your way through the dungeons.
81-82
Most of the Heroic Burning Crusade Dungeons will stop giving you xp at this point, so go and do some of the raids. Serpentshire Cavern has level 72 10 mob pulls which you can AoE in seconds and give massive amounts of xp.
83-87
Unfortunately this is back to questing and queuing yourself for dungeons. These levels can seem like a bit of a grind after coming off the rocket fuel of 74-82. At 84-87 you can solo heroic Northrend dunegons, but I'm unconvinced that this is faster xp than questing. It is however a very good moneymaker.
Author's Note: I found Heroic WoTLK dungeons tough at 83, and noticeably easier at 84. I found I had to grind out 83-84 by questing/LFG & BG's, basically any way I could.
As I mentioned, I'm unconvinced 84-88 using WotLK Heroics is actually faster than questing. It's certainly profitable, I had a string of epics drop which people bought for silly prices on the AH, and the trash alone made me a number of thousand. It's decent xp, but I faster is up for debate.
Sircowdog's addendum: 82-84 you can actually solo normal Ramparts at a reasonable speed. I think each level took me ~15 minutes, running around 1-1.2 million exp/hour according to titanpanel. At 85 the experience was cut cleanly in half. Might still be worth it to keep running if there's no better options. 30min/level isn't terrible compared to questing.
Sircowdog's addendum 2: Northrend Dunegons are the same level for normal and heroic, making the enemies worth the same regardless. It ends up being the same rate as Ramparts normal, and Ramps is the shortest/fastest of them all.
88-90
Heroic Zul'Gurub is your friend. Solo the dungeon in a big circle avoiding all the bosses and killing all mini-bosses. Get back to the start, exit, reset, and do again. 5 circles and resets should be enough xp to go from 88-90.
Doing loops of Zul'Gurub as I mention 88-90 killing just the mini-bosses and resetting is definately faster however (and again, profitable). I powered through those levels in no time at all.
90-91
Was simply the intro quests to WoD.
91-98
Go grab a 630 weapon from a friendly guildie (best) or AH (worst) and you'll OP everything you hit. You're literally doing 2x the similar heirloom weapon damage I found. For me 91-98 was actually one of the funnest parts of the leveling. I grabbed engineering and made myself a ton of Mecha-Rockets which are hideously OP in random battlegounds at this level. I play on a server/battlegroup on which the 91-99 random Battlegrounds were popping approx every 7 minutes. So I simply Battlegrounded most of my way through the levels, I hit 98 having barely done 1/4 of the quests in the starting zone. Winning in 91-99 battlegrounds gives a ton of xp, with some BG's giving me half a level for 15 mins of good fun. A string of wins clearly helps here, but armed with your OP mecha-rockets I found my win/loss ratio was more than OK and it was great fun too.
I'm guessing the above is only useful to you of course if your BG queue times are as low as those I had, and you enjoy random pvp.
All of the above is obviously class and spec dependent in terms of how easy it is to do. Certainly if your class has a tanking spec or healing spec, particularly a tanking spec, you'll see a lot of the insides of stockades and ragefire the first 40 or so levels, but blast through the completion xp.