After the latest patch, the lighting looks very weird for me in the Grove:
The whole bottom floor (underwater, everywhere) is overlaid with that fuscia and white checkerboard light. Appears in my home instance too. In addition, the usual ambient effects - sparkles, lighting - are not present.
Restarting the game client didn't change anything. I have the settings on "Best Appearance" in this screen grab. Not sure if it's affecting any other areas of the world at this time.
Edit: It's definitely on other maps too. Guild hall is especially noticeable - large chunks of the floor tiling is replaced with this pattern instead of their usual effect. Changing the settings to "Best Performance" doesn't make a difference as far as this issue.