I think that kind of horserace stuff is ultimately just as irrelevant to movies as it is to political campaigns. It's stuff that journalists talk about so they'll have something to talk about. Once the movie comes out, few people will remember the hoopla that happened at this early stage. They'll judge it by the actual content, not by the "buzz" way back in the summer of 2013.
I'm inclined to agree. Seriously, has there EVER been a high-profile comic-book flick where there hasn't been some sort of on-line tempest or controversy along the way?
Off the top of my head:
Michael Keaton as Batman. Too much a comedy actor, too small, too balding etc.
Val Kilmer as Batman: too blond.
Stallone as Dredd: took off helmet.
Ian McKellen as Magneto: too gay (seriously, at the time some fans were up in arms about this)
Hugh Jackman as Wolverine: too tall, too young, Australian rather than Canadian, not muscly enough, Logan can't be played by a song and dance guy. Probably gay too.
The X-Men's black leather outfits. Damn Internet nearly exploded.
Anna Paquin as Rogue. Too young. Accent wrong.
Halle Berry as Storm. Should've been Angela Bassett.
Spider-man's organic webshooters and Green Goblin's Power Rangers outfit and mask.
Daredevil being played by Ben Affleck (him again). Daredevil's leather outfit. Jennifer Garner not being Greek. Colin Farrell being Irish. Michael Clarke Duncan being black.
Topher Grace not being muscly enough to play Venom. Changing the symbiote story.
Ras Al Ghul being Japanese instead of Arabic. Wait, he's actually Irish? WTF? Even worse. Scarecrow being a young good-looking guy instead of a tall skinny middle aged man. Christian Bale's speech impediment.
Jessica Alba as Sue Storm. Too Latina. Pretty much everything about FF except Evans and Chiklis. Somewhat justified in this case.
Halle Berry as Catwoman. Apparently the film was crap, not due to bad writing, directing or SFX, but because she was black. That and her costume.
Superman Returns' costume.
Heath Ledger as Joker. Internet nearly exploded again.
Vinnie Jones as Juggernaut. Kelsey Grammer as Beast.
Robert Downey Jr as Iron Man. Internet explodes again.
Tom Hardy as Bane - too small and not muscular enough. Anne Hathaway as Catwoman. Not sexy enough, apparently.
Ben Kingsley as Mandarin. Insufficiently Chinese (wait till they see the damn movie).
Chris Hemsworth as Thor. Idris Elba as Heimdal. Tom Hiddleston as Loki.
Chris Evans as Captain America - why, he's already been The Human Torch!
The Eric Bana-Ed Norton-Mark Ruffalo saga. The Terrence Howard-Don Cheadle saga.
Michael Shannon as Zod. Insufficiently famous or British. Man of Steel costume.
Karl Urban as Dredd. Chin too small.
Jamie Foxx as Electro. Looks too much like Mr Freeze.
David E. Kelley's Wonder Woman. Where do I start?
I'm sure I've missed plenty. Any advances?