This is more speculation than news, as the title implies, but bear with me. As has been discussed already, Sega has some undisclosed "bombshell" announcement for E3. Some theorize that it might be a new console. Well, there may be reason to believe that Shenmue might play into whatever the announcement is. As Shenmue Dojo's Shenmue III preview points out, the Shenmue.com official site has been redesigned very recently. Why would the website of a game series that has no announced future release be redesigned? The new design is snazzy but lacks content - suspiciously like a website that is expected to host a lot of stuff later (empty areas for future menu items and such). While it's doubtful that Shenmue 3 itself would be Sega's "bombshell" announcement, it's not hard to imagine S3 being a part of the larger whole - perhaps a launch title for a new console?
News source: Evilavatar.com