A very helpful summary of Eastern Orthodoxy, in light of the conversion of Hank Hanegraaff to Eastern Orthodoxy. (by Sam Storms) (Posted by Pastor John Samson at Effectual Grace. Samson links directly to Storms’ article.)
Addendum: And more to see for further study:
Historical Theology and development of Doctrine in relation to Roman Catholicism and much of it also relates to traditions and early church history and applies to Eastern Orthodoxy.