Resident Evil 6 will also be in the spotlight as part of its own stage. Capcom promises "first Japanese reveal" information for the stage. The wording makes it sound like the event will just recap announcements made previously overseas (presumably during E3), but we'll have to tune in to the event to be sure.
Capcom Summer Jam will be held on June 30 and July 1 at Tokyo Big Site.
Capcom was previously promising an update on the event for the 31st, which is tomorrow. The MH4 and RE6 stage details were quickly removed after posting, so it's possible that this was an early leak.