Sure, the image is a bit dark, but trust me, the guy has blue skin.
Gunn had this to say about the character and the actor on his Facebook page:
#gotgpicoftheday Michael Rooker onset as Yondu. You’ll be seeing more of him soon. Yondu was not in the original script. I added him and wrote the role specifically for Rooker. I wasn’t sure Marvel was going to go for either idea, so I was relieved when they responded enthusiastically to both.
And while this is the first official Yondu image, some unofficial pics were leaked from location filming earlier in the year. Like other characters in the movie, Yondu’s onscreen personification fits the spirit of the character while not being a dead ringer for the guy on the comic book page. (Unless there’s a major CGI assist to his dorsal fin in post…?)
GotG will be released on Aug. 1.