Well this does tie in with a rumour I heard from a "good" source, but I don't want to say who in case he wasn't supposed to say anything.
Essentially though there are big changes coming 40K wise, and a couple of releases have been held back for just such an event.
I would have said next year was more likely, but then again this year is just as possible.
Marines should be getting a flyer this year, Chaos should be getting a Locust equivalent and tau should get something next year.
I hadn't heard about Orks, but I would be very surprised if they didn't get something too.