Invitations and Becomings

I've been reading the Terms & Conditions on the Bright Kite site (yes, I do that sometimes), I came across this pearler:

"What’s yours is yours. You own your User Content, not us. You grant the Company and its affiliates a perpetual, irrevocable, worldwide, non-exclusive, royalty-free right and license to use, reproduce, modify, adapt, publish, translate, create derivative works from, distribute, publicly perform and publicly display your User Content (in whole or in part) and/or to incorporate such your User Content in other works in any form, media, or technology now known or later developed. You also grant each user of the Site the right to access, display, view, store and reproduce such your User Content for personal use. You represent and warrant to the Company that you have the right to grant the licenses stated above."

I can't think of a relevant definition of "mine" that grants you a "perpetual, irrevocable, worldwide, non-exclusive, royalty-free right and license to" do whatever the hell you want with "my" stuff. Wouldn't it have been more accurate to start with: "What's yours is ours"?