A lot of web sites have a Word Document download that includes both the template for the submission and the WotC release form with the Wizards logo at the top.
That copy of the release form is not binding and will not be accepted. You have to use the PDF release form, available through Wizards' own web site.
If you've already sent your submission with an "improper" release form, you'll be contacted by WotC after they receive it and given an opportunity to "correct" this mistake.
Needless to say, I read this from Anthony Valterra on the ENWorld forums five minutes after I'd dropped my submissions--complete with the wrong release form--in the mail.
Would it have been that hard for them to make this clear earlier?