It seems that there is a rumor of one of the special features on the Looney Tunes Golden Collection Volume 4 on the Golden Age Cartoons forum.
The rumor of a Friz Freleng documentary to be exact.
Friz Freleng introduced and/or developed several of the Warner Bros' biggest stars, including Porky Pig, Tweety Bird, Sylvester the cat, Yosemite Sam (to whom he was said to bear more than a passing resemblance) and Speedy Gonzales.
Hopefully this is true!
It is also rumored that there is going to be a disc dedicated to Speedy cartoons.
Arriba, Arriba, Andale!