It won’t be officially official until Marvel makes an announcement, possibly at Comic Con later today. According to The Wrap, though, the deal is almost done, and the goal is to finish everything up so Ruffalo can fly over to San Diego to join his fellow Avengers in Geektown. The sticking point, as with most Marvel movies, is the studio wanting a major commitment and multiple films from the actor, while not paying a whole lot for it.
If the deal gets done and Ruffalo shows up, it’ll be a grand entrance, no doubt. At least, for those in attendance who aren’t still holding their breath for Edward Norton to reprise his role as Bruce Banner aka the Hulk’s mild mannered alter ego. Things could get a tad frisky there when the announcement is made, I’d imagine.
Look for an official “Tada!” confirmation tomorrow … or possibly not.