Thats not true - if you take a look at
www.wowprogress.com or any of the other similar sites to compare realm progress - you will see that tons of the top pve guilds are based on pvp servers.
That said there are enough servers out there that you will find a decent server on either pvp or pve if you do your research properly. Rather make your choice between pvp/pve based on how you enjoy the different styles. If you're looking for a new server to transfer to you should do some research though into the following:
- Take a look at WoWProgress.com on your proposed server or something similar and see how many guilds are farming ICC atm - if you have tons of guilds farming the top instance - it means there will be lots of alt/pug runs usually and there are plenty of guilds to apply to
- Also do a search on WoW census and see what the alliance horde/ratio is - an even ratio usually means better world pvp or more competitive wintergrasps but it also might mean that you don't always dominate wintergrasp which can be a pain if you want to do VoA
- Create/log in a level one alliance & horde toon and do a /who wintergrasp in at busy time and see what the numbers balance is like - also do it on a few nights at different times and see who controls wintergrasp the most
- Use the level one toons to monitor trade chat a bit - see how many pug raids are being formed - if there are a lot of pug raids or old school raids - its a pretty active server
- Use the level one toons to go take a look at the AH and see what the prices are like (before you move see if there is anything you can buy for cheaper on your old server and sell on your new server for profit)
- Go read the realm forums - watch out for complaints about foreign nationalities - if you're aiming for an English server - you probably don't want to be stuck on the 'unofficial' greek server. Again see how active the forums are and how many guilds are recruiting and what classes.
- If you don't mind being a pain and getting some flames - ask a few questions in trade chat about the server, how they do in bgs etc.. etc.. you'll usually find somebody willing to answer a few questions