I'm also suffering from this problem as well (DFW area/fios), but I'm 99% certain that its a routing problem with the Aether and Primal datacenters. I can connect to the chaos datacenter, which is in the same subnet/facility without any trouble. But, when attempting to connect to Aether (199.91.189.74), The connections starts up fine, does the little tcp handshake, but then the server (199.91.189.74) starts sending me tcp packets with the wrong seq. number, even though I have no packetloss with pings or traceroutes. now, the traceroute doesn't look that great, some issues with verizon to level3, and from level3 to SquareEnix, but those look identical to the chaos datacenter, where I have no problems.

I have been able to still get into the game using a vpn service, (WTFast, or private internet access, or any vpn that gets you around the dfw level3 router.