Thalassian Base Camp (marked BLUE on the map) - Some Blood Elves have set up a camp in the northern parts of the Azshara. Blood Elf Reclaimers and Blood Elf Surveyors that can be encountered in the said camp are rather easy to kill and have very good Loot Table. The most notable items dropped by those Elves include Runecloth, Mageweave Cloth, 16 Slot Backpacks, various Vendor Trash Items (junk weapons, armor, and so on), and Pocket Money. They can also be Pickpocketed, so this spot presents an additional value for Rogues. Blood Elf Reclaimers have access to strong Fireball, Heal, and Renew Spells, so they should be interrupted when possible and prioritized. Recommended Level - 52+ (54+ to be extra safe, and farm Elves at an increased pace).
Tainted Oozes (market GREEN on the map) - Oozes infest Felwood in great numbers, and although they do not have too good Loot Table, they might be still worth Grinding. This spot is a long shot, so be warned. Felwood Oozes have a small chance to Drop Oozing Bag which in turn has a small chance to contain the Disgusting Oozeling Pet (this pet is used to throw off various Debuffs in Raids, so many Guilds will require you to have it), the Bag can also contain various Potions, Herbs, and Gems. Oozes themselves drop a lot of low-value Vendor Trash Items and some Pocket Money (they can also be Pickpocketed, so Rogues might be more interested in this spot). Recommended Level - 50+.
I really can't buy into this reason because they used to do beta without the subscription requirement. It seems like if they want to test how many people are interested, they can just open it up to everyone like they do for every WoW expansion. And how are they going to know how many servers they need for all the people without a subscription who can't reserve a name or qualify for beta?
Pick the Right Professions - Professions will amount to a very large portion of your Gold income if you pick the right ones. We will cover this subject in much more detail in the next section of this Guide, but here is a TL/DR version: Gathering Professions are generally better on new servers (for example, Skinning provides you with some extra money for every single Beast that you slay in the world, even if you just vendor the gathered Leather), especially if you are leveling quickly, as Crafting professions require a lot of Time and Gold investment to level up (but they get much better when you are leveling slowly and during the End-Game, because then the ability to craft some gear starts to outvalue the ability to make a quick profit).
The Horde 12-20 (Barrens + Stonetalon Mountains) guide has been rewritten and revamped.  In addition, there has been numerous tweaks to the speedrun route to make things faster and easier to follow.  Also, in case you haven't noticed I am now adding about 40% more info per step and redoing all the images.  Unlike with my previous vanilla guides, I am now giving a brief explanation of where to go and what to do with each step along with any other helpful tips.