Last week, The Game Awards host Geoff Keighley announced Summer Game Fest, a four month long digital event showcasing upcoming games. Microsoft's Inside Xbox event on May 7 will be the start of Summer Game Fest, and Gamescom on August 24 will serve as the finale.
Following the Inside Xbox presentation on May 7, the next Summer Game Fest event will take place on Tuesday, May 12 at 9am PT. Entitled Sunrise #1, the event will consist of a surprise game reveal.
Recently Keighley posted a list of developers and publishers participating in Summer Game Fest, including PlayStation, Xbox, and digital storefront Steam, along with major third party publishers such as Activision, Bethesda, CD Projekt Red, EA, WB Games, Square Enix, and more. The initial list of collaborators is dubbed "Phase 1," therefore it's safe to assume that in the coming months more teams will join the festival to show off new titles.
While the title of this presentation states it will be a "surprise game reveal," it can be speculated that the reveal may not only be alluding to the announcement of a new game entirely, but rather an update to one that has already been announced. That said, the more likely scenario may be that this could be the first chance we get to see the next installment of the Call of Duty franchise, given that a new title is usually announced in May, and that Activision recently stated that the next entry is still on track for a 2020 release. This is all speculation though, as given the amount of collaborators promised to be participating in Summer Game Fest, it's hard tell what Keighley could have up his sleeve.
While it's hard to nail down what the announcement itself could be, we can safely assume that it will not be coming from Microsoft, given that it has already outlined its plans for announcements this summer, with a presentation dedicated to first party titles coming in July. It's also unlikely to be any sort of update on Assassin's Creed Valhalla, given we already have confirmation that we will be seeing gameplay footage of it at tomorrow's Inside Xbox.
Summer Game Fest begins May 7th and ends August 24th, the first "Sunrise" presentation will take place on May 12th at 9am PT/ 12pm ET/ 5pm BST.
Source: Summer Game Fest website