Mt good friend Master Exploder pointed this out to me and I thought that some folksthat play Eldar would be interested. This was news to me, may not be to some of you.
The new Dire Avengers squad box comes with enough parts to make 2 Exarchs, with all the trimmings. The Eldar Autarch, especially the one that comes in the Army box, looks very much like a Dire Avenger Autarch.
If you were so inclined to have an Autarch in your force, use the extra Dire Avenger Exarch parts. The Shimmershield works greats as the Autarchs Forceshield, and you can arm him with a power weapon and a shuriken pistol very easily. A little putty work can make you an Autarch-y cloak and sash around the waist, and you can use both the Exarch banners to make the double Autarch war banners if you wish.
A little cutting and sanding would remove the Exarch's trademark hair crest, and then a little sculpting would get you the hair plume that the Autarch has, if you desire it. Or, just sculpt on some Mandiblasters or Banshee sonic amplifiers.
This is also a great way to get an easy Jetbike Autarch instead of hacking up a metal Autarch. You could even rep the Jetbike Autarchs laser lance (what other weapon would you give him, honestly?) with the Exarch power weapon-glaive-spear thing, with a little converting.
Just thought I would drop that into the pool for you Eldar commanders.