The flowers! The cake! The guests! The bride -- in yellow? Fall Out Boy's Pete Wentz wed alleged baby mama-to-be Ashlee Simpson -- now, "Extra" is breaking down the five biggest "I do" rumors surrounding the Los Angeles ceremony!

Cameras outside the ceremony snapped Ashlee sashaying in a yellow dress -- did the unconventional singer opt out of the traditional wedding white? No -- the bride wore an ivory Monique Lhullier wedding gown. Amid breakup reports, did big sis Jessica lasso Cowboy QB Tony Romo as her date? Yes -- the two arrived to the exclusive nuptials together, though reports say after the wedding Jessica and her parents hopped a jet to Mexico -- without Romo.

Papa Joe Simpson, a former Southern Baptist minister, performed the ceremony perfectly in front of 150 guests -- but things got hairy with the ring bearer, Hemingway! Wentz's beloved English bulldog walked down the aisle with ring in tow.

Ashlee and Pete did break with tradition for their reception with an Alice in Wonderland theme. The wedding cake came complete with décor from the Lewis Carroll tale -- including a top hat, tea pot and flowers.

Click on an image to view the ASHLEE SIMPSON photo gallery!