In a very rare move indeed, Marvel Comics has the front cover of Previews for Civil War II #0, out in May. The deal between Marvel and Diamond has their own section of Previews rather than being lumped in with all the others and subject to Diamond Previews' more favourable initial deal with DC Comics, after the original exclusivity agreements. So it's very rare indeed for Marvel to appear on the front cover of the monthly catalogue.
But it looks like Civil War II was enough. DC's Scooby Apocalypse cover by Jim Lee (yes, that Jim Lee) takes the back cover spot. And Gene Ha's Mae for Dark Horse also gets a mention.
They also put Captain America: Steve Rogers on the front of that Marvel Previews catalogue.
And Avatar Press' Cinema Purgatorio which hit $110,333 in funding yesterday, and launching at London Super Comic Con this weekend, is on the front of the Customer Order form.