I pinged this on the stream a bit, but here's the scoop:
In the hopper right now are SLI and Crossfire support (driver support will help this too) - should be in a hotfix soon (I think some support went in earlier this week). From the lead programmer:
"For those of you with SLI and Crossfire graphics cards. The code changes have been made to support these cards are done and are being tested internally. Those of you with these cards should see a substantial improvement in frame rate."
(JG: substantial is his word, not mine

But being able to use both cards will help a lot; I run a dual titan setup which runs just fine at the moment but I'm looking forward to this upgrade too)
Other stuff from him (this will likely go up on the forums soon in some fashion, maybe edited further, so if it changes before it goes up, that's why):
"We’re also optimizing our new UI. The new UI (UI 2.0) is much better looking than the previous version, but there are significant opportunities for performance improvements that we’re pursuing. In particular, the raid frame and nameplate add-ons are being improved. There were also major changes to chat log, target frame, and the health shield bar.
We continue to increase CPU performance by moving more and more code off onto separate threads. We’ve also been making improvements to PVP and Raid content - areas with lots of players casting spells.
We’re also looking at specific areas in the game which have degraded performance. Sometimes these are due to bad collision objects, bad geometry, or the occasional content bug. We’re eliminating these as fast as we can find and diagnose them.
Our optimization efforts will also not stop with launch. There are a number of changes we’re planning on making which have the potential for major improvements but that can’t be done in the launch timeframe.
In the meantime, there are a number of graphics settings which can be used to coax better performance out of the game. We’re planning on adding the Render Target Scale back in to the graphics options, but until we do, you can set the variable in your ini file by adding the line
lod.renderTargetScale=0.5
to your user.ini file in Users[User Name]\AppData\Roaming\NCSOFT\Wildstar. "
So, yes, there are things going in for launch - we don't promise perfection per se, but hopefully the worst offenders will see some improvements, and there is more in the hopper (some rearchitecturing for instance that will let us split thread support even more efficiently) for post-launch as well.
-jg