Sometimes Hollywood DOES listen.
From what ive read, its not a CGI tomcat, or at least not completely. They have gone through the archives, presumably of stuff they shot for the first one, and other stuff filmed elsewhere pre 2006, of real tomcats in flight, and just digitally altered the livery on it to match what they filmed on deck. Or at least, that is what one article claimed. So hopefully we will be spared any Pearl Harbour or Dauntless sillyness of it behaving like an S4 Flying Saucer.