Hi am new to WOTLK (good knowledge of TBC however)

I wanted to try WOTLK so here am I.

MY questions:

1) which fraction. I am mostly interested in PVE, therefore I will take the fraction were it is easier to find a raid group. Best would be of course cross-fraction were it is possible to raid with horde and allianz together. Also is there much open-pvp? I hope not I hate it if I get killed outside. If I want to do pvp I go for battlegrounds.

2) which class. Really I know classes in TBC but not really in WOTLK. One of my favourite classes was affliction warlock. However due to crit and haste on items later on the class became boring by spamming the same spell over and over again. Due to dual talent I would also like a class which could do several things at once, tanking/dd/healer. Just give me suggestions which classes are most needed. Since this is my first char on this server a very gear depended class like warrior would not be a good choice.

3) which professions are useful and which are not.

4) What is important in WOTLK, call things I should know. For example in TBC it was very stupid to do quests first. It was much better to kill certain mobs first until you was friendly and then doing quests.