To stop all the conjecture about the new council of tirisfal this is a list of confirmed members of the new council... this information is taken mostly from the wow comic and the following members have been asked and accepted to join the new council:
Jaina Proudmoure - If you dont know who she is then you probably shouldnt be reading this.
Meryl Winterstorm - an undead mage who served on the original council in life, while not a true forsaken he keeps himself alive by the power of his own magic. He is also the father figure to Med'an having raised the boy most of his life. He has also recently been possesed by a powerful demon, and is struggling to keep the demon inside him at bay... he has begun to show signs of demonic influence using fel magics to empower his own, implying that he may bring a warlock perspective to the council at a later date.
High Priest Rohan - The dwarven high priest of ironforge, friend of meryl and renowned weilder of the light. He will represent the priest style of divine magic on the new council.
Krank Axeljink - A gnomish inventor of tinkertown, friend of meryl and rohan, it is unknown if he has any magical affinity but his inventions typically involve using or altering the flow of magic. his latest invention involves merging nature, divine, and arcane magics into a machine that he believes could help alter the traditional ritual that empowers the gaurdian to include the other types of magic, however the reciever of these would still need affinity in all 3 types...
Hamuul Runtotem - Tauren Archdruid of the cenarion circle, student to malfurion stormrage, and the most powerful of the hordes druids. he will represent the druid style of nature magics on the new council.
Rehgar Earthfury - Powerful orc warrior turned shaman, ex-arena master, personal advisor to thrall, he represents the shamanistic style nature magic on the new council.
Valeera Sanquinar - A skilled bloodelf rogue, daughter of Relfthra a deceased member of the original council. While she does not practice any forms of magic she has a strong affinity for the arcane but is in danger of becoming addicited if she further exposes herself to it.
Maraad - A draenei palidian, vindicator of the naruu, and great-uncle to med'an. He is the uncle of garona and has been teaching med'an divine magic. He will represent the palidan style of divine magic for the new council.
Dalynnia Wrathscar - A blood elf mage, student to khadgar, magistrix of the scyrers. She will represent Arcane spellcasters on the new council alongside Jaina.
Med'an - The prophecised savior of azeroth, likely canidate for the new gaurdian as he can wield divine, arcane and nature magic together with great skill and power, he is the son of the last gaurdian of tirisfal medivh and garona half-orcen. he is 1/2 human, 1/4 orc, 1/4 draenei.
Aegwyn - While she has no power left to fight and is drained of her once great power she will still sit on the council as an advisor to teach them the ways of the original council.
The following are people who were considered for the council but either rejected or were unable to be reached:
Brol Bearmantle - A poweful nightelf druid who served in many wars and also under rehgar as a gladiator. He was considered to represent druids on the new council but he was busy with personal affairs in darnassas and could not be reached. he may still join the council at a later date.
Thrall - Jaina asked thrall personally to join the council to represent shamans.while he expressed interest in joining he is to busy preparing for the battle against the lich king to accept, he instead sugested that rehgar take his place representing shamans.
Khadgar - Khadgar was asked by maraad to join the new council but he turned down the offer to stay with adal in shattrath, he instead sent his student Dalynnia to represent arcane magic users in his stead.
As it appears right now Med'an WILL be the new gaurdian of tirisfal, it has been discussed many times in the comic that he is the only person able to withstand the incredible power of weilding all 3 types of magic effectivly due to his mixed heritage and natural talent due to his parentage.
This list is subject to change.
EDIT: Updated Meryl winterstorms profile to include his demonic possesion and the fact that he may come to represent warlocks on the council if learns to control the demonic energies inside him.
DEFINITION OF A GUARDIAN - There seems to be some confusion as the what exactly a guardian of tirisfal IS. yes they are a protector of azeroth but some people dont seem to understand the unique circumstances involving the creation of a guardian of tirisfal.
from wowwiki:
What that means: The gaurdian isnt just a powerful individual chosen by the council to defend azeroth, the gaurdian is a CHAMPION who recieves a portion of each of the council members powers to become and unstopable force.The Guardian of Tirisfal, also known as Guardian of the Tirisfalen, was a single mortal champion magically empowered by the Council of Tirisfal to secretly fight the Burning Legion and other demons wherever they may appeared on Azeroth.
It was an order of immensely powerful beings who were empowered to protect the world from the Burning Legion over the millennia. The Guardians were imbued with powers from all members of the Order of Tirisfal, becoming extremely powerful in their own right.
There can be only one Guardian of Tirisfal at a time. Each Guardian of Tirisfal is empowered through a long ritual by a council of seven archmages. The secrets of this ritual are closely guarded, if not all but forgotten in recent times. A new Guardian of Tirisfal cannot be empowered while the previous one exists. Only through his death, or through an equally long and secret disempowering ritual conducted by the surviving archmages who empowered him, can a Guardian of Tirisfal be stripped of his power.
in the past the council was made up of just mages, so the gaurdian became any incredibly power mage, but now that the council consists of more then just mages, it also includes shamsn, druids, preists, palidans, the guardian would have to be able to withstand immense powers the magics create when they are mixed, something no ordinary mortal can do (quoting Aegwyn here). fortunatly for all us we just so happen to have the exception to the rule in a boy who can never seem to find a shirt his size.
Med'an can, and has, used all 3 types of magic together, due to his mixed heritage and and the immense power associated with his bloodline (his father and grandmother both served as pervious guardians.) hes the ONLY likley canidate for gaurdianship as it stands now.