So I am almost at 70 with my Human Warlock, and I'm looking to experience the Horde side and I've tried out both a Warrior and a Priest and I honestly really liked them both a lot, so I figure I want to heal or tank with this new Horde character, so generally does this world need more healers or tanks?

If I were to be a healer what are the advantages/disadvantages of each class and same with tanking? I would like to PvP as well, so if I could get some pros and cons about some of the races and classes for tanking or healing that would be awesome. Thanks for the help!

Both are in HUGE demand.

On detheroc, its nearly impossible to find any Holy priests or Tank warriors before level 60, and still hard then. Every warrior is fury and every priest is Shadow.

If you really like them both, combine then and become a druid or shaman.
preferably i like druid more, but that's because i'm one myself

with a druid you can tank (bear) or dps (cat, or moonkin with balance spec) and heal (resto or just good healing gear)

With a shammy, you can do all that too, but it cost mana for everything. Enchancement is dps spec, but you use more mana for stuff. and Totems in pvp are useless, since most have 5 hp

The problem with a druid, is that you don't become a melee class untill lvl 10,where you get bear form, and at 20 cat form, for dps.

Shammy on the other hand just has to learn skillz, which you basically get at lvl 1 -_-

It's up you though, be a priest, rogue, warrior, anything is advantageous in WoW, altough healers are probably more needed.

hmm druid : 45% healers 45% tanks 10% dps but only 2% of ur realm is gona be druid so u could go for that but u find it hard to gain agro or do quick heals
in my realm it is in total 70% dps 20% tank 10% healers