UPDATED 6/29/2016 11:10 AM PT: Marvel Comics as released an updated version of this Alex Ross-illustrated Marvel NOW! teaser -- the visual remains the same, but the words "I QUIT!" have been added, along with the date of July 5. That's this coming Tuesday, so, presumably, more information about exactly what this teaser is teasing will be coming along then.
The image -- of Ms. Marvel, Nova and Spider-Man (Miles Morales) burning their Avengers ID cards, was first seen a week ago as the cover of the July 2016 issue of Diamond's "Previews" retail catalogue.
Original story, June 22, 2016: Marvel has released a new teaser for the upcoming Marvel NOW! initiative, and it's not like the ones we've already seen this week. This time around, the image is an Alex Ross cover featured on the July 2016 issue of the industry mag "Previews."
The image sees Ms. Marvel, Nova and Spider-Man -- the teen members of the current Avengers lineup -- burning their membership cards, possibly renouncing their membership with the group. Where the image will end up remains unannounced, although considering the artist and characters, it's possible it will be featured in "All-New All-Different Avengers."
The scope of Marvel NOW! will be unveiled with the release of the "Marvel NOW! Free Previews Magazine" on July 13.