WGT does have it's moments, but that's true of any website.
The only thing that is consistently slow are web page loads, but I figure that's because bandwidth priority is given to game play.
One thing that will slow you down is having background loading turned off.
I used to play with it off to help my meter, but since I started closing my browser and turning a few more things off with Game Booster, things still run smooth with it on and game loads are much faster.