The pylons aren't working after you complete all of the chain quests. You can't get the Power Crystals from them. I understand these are needed in the Libram quests, well some of them. Which aren't accessible to us, but if there is question whether these are 1.4+ items or not. They were included in 1.3 in March.
http://www.wowwiki.com/Power_crystals
http://www.wowwiki.com/Crystal_Charge
http://www.wowwiki.com/Crystal_Restore
http://www.wowwiki.com/Crystal_Force
http://www.wowwiki.com/Crystal_Spire
http://www.wowwiki.com/Crystal_Ward
http://www.wowwiki.com/Crystal_Yield
