by Valandar » Mon Dec 14, 2015 10:34 pm
There are lots of other threads that cover this, and have good informational posts. Look through a couple of pages in this forum for more info. Honestly the best thing to do is create a character on each realm, and then look at the starting zones. After that head to a major city and check out the pop, and talk to some people there.
PvP Server is older, so it will take longer to catch up. However, more people so easier to find groups and people to help and play with. More established / successful raiding guilds on PvP because they have been around longer.
Also, PvP server is alive with world PvP. Since the population is so high there is always ganking and people dying, so if PvP while questing isn't your thing PvE is the best bet. The huge pop also has cons because of some lag spikes during peak times when the server hits 8k+ people. And lots of fighting for quest mobs / items (which I like personally). It isn't very bad though.
PvE will be newer, so you will get to see the release of more 1-2 more raids (if you care about that). More people leveling, less established 60s. No world PvP so questing is easier, but no awesome battles unless you flag yourself. Less people, so not as much crazy competition for mobs/items, but harder to find groups sometimes. It takes longer at least, but you'll find a group.
Just two complete different servers, try them out and decide yourself.