CCP GingerDude has posted a new blog to address some of the lag issues that have been plaguing EVE Online since the deployment of the Dominion expansion, a topic that The Mittani has covered on numerous occasions. It seems that CCP has tracked down the cause of the lag. I'll let CCP GingerDude speak for himself on the issue:

When anything is added or removed from a ticking solarsystem, a lock must be held to ensure that the operation isn't interrupted during critical paths.  This includes the case when you're attaching the aforementioned client session to the system.  If a fleet jumps into a highly loaded system, a queue of client requests forms waiting on this lock and this is where you're stuck; server handover part has completed, so you're "there" as far as the server is concerned, but your client never finishes attaching to it and thus never gets the initial solarsystem state.

The positive side is that some changes were already in the works to help address the problem; however, what has been added may not exactly fix the current issues.

Now, much tighter locks don't lighten the load on the server at all.  The same amount of work still needs to happen for any given jump; we're just mixing the tasks up better so it's fair to those wanting in on it. In effect it means that someone else blocks you a lot shorter when you jump, which means you get added to the fight at the other end sooner allowing you, dear pilot, to activate your modules and drones and whatnot and thus actually adding to the existing load and increasing the existing lag. 

It would appear that CCP has figured out a lot of what's causing the issue, but it may still be some time before EVE Online can function at pre-Dominion levels.