...

...

For the same reason that cc-by-sa is often preferred to cc-by. The viral nature of share-alike -- which is what the GFDL amounts to -- means that reusers have to put modifications under the same free licence. This means that the content is more free and therefore furthers our mission.

And...? ;-)

I actually deleted my next sentence from my post for fear of being flamed: "I personally disagree with this and think that the fewer restrictions placed on work beyond simple attribution the better."

(I license my work cc-by.)

Thought of saying so on your user page e.g. {{DualLicenseWithCC-By-2.5}} ? You currently have cc-by-sa.

I really doubt you'll get flamed for it.

-Dan