There were awesome "Know your enemy" articles. Wowhead articles are fine but those were good in terms of PvP especially for those who've just returned or got into the content and want to catch up fast.
Quick recap of class abilities, dangerous CDs to watch for (copy to Omni bar), some tricks and not obvious mechanic interaction. (Like mass dispel and divine shield STILL MEET PEPOLE WHO DOESN'T KNOW THAT)

Thank you!