This post obviously spoils the end credits tag of Guardians of the Galaxy.
There are two kinds of tags at the end of a Marvel Studios movie. One is a portentous set-up type of tag, featuring hastily shot footage from an upcoming Marvel movie. Think Baron von Strucker at the end of Captain America: The Winter Soldier or The Collector at the end of Thor: The Dark World. These tags tease upcoming movies in the Marvel Cinematic Universe but, to be fair, they're also often sorta bad. Anybody watching that Collector tag would have thought that Guardians was going to look like shit, which it demonstrably doesn't. It's just the nature of turning around something like that with speed.
The other kind of tag is the fun button. Think the shawarma scene in The Avengers or Bruce Banner listening to Tony tell the tale of Iron Man Three. Sometimes the tag is even the actual end of the movie (see Thor: The Dark World). I like these tags as well; while the teases get my heart racing as a nerd, these funny and sweet stingers warm that same heart as a fan of the movie I just watched.
The final tag on Guardians of the Galaxy is somewhere right in the middle of those two, and it's left some audiences baffled. I'm not talking about sprouting Groot dancing - everybody gets and loves that. I mean the very end, where we return to Knowhere and find a bruised and bandaged Collector being licked by Cosmo, the Russian space dog. We hear someone say "You let him lick you like that? That's disgusting!" and the camera reveals... Howard the Duck! He was in The Collector's menagerie all along.
Taken on its own, this tag is just a funny bit at the end of the movie, a little laugh moment that comes equipped with a bit of a shock. Who thought that we'd ever see Howard the Duck on the big screen again? Especially considering Guardians made almost as much in Thursday night showings as Howard the Duck did during its entire release. It's simply hilarious, and my theater last night was filled with people yelling "WHAAAAT?", a great reaction.
But wait! There's more! See, the Howard the Duck cameo is kind of a mission statement. It's letting us know that Guardians of the Galaxy is set in a corner of the Marvel Cinematic Universe that's even weirder than the previous two hours led us to believe. And that no character, however silly, however much a 'failure,' is off-limits. It's also saying something that only true comic book fans will get : that James Gunn and company understand what is actually cool in the Marvel comics universe, because Howard the Duck is totally fucking cool. Most people only know him from that disaster of a movie, but the reality of Howard is that he's a funny, acerbic and smart bit of satire that predates and deeply informs Cerebus the Aardvark, generally held as the 'thinking person's funny animal.' Gunn gets why Howard - who mounted a presidential campaign in 1976 - is a character worth rescuing from the dustbin.
On top of that the sting lets us know that The Collector is still alive and kicking; as an Elder of the Universe I'm sure he has more to do in upcoming Marvel cosmic movies. And I'm sure they have Benicio del Toro in one of those six-to-nine picture Marvel deals anyway.
One last thing this stinger tells us: Marvel is in no hurry to connect Guardians to the rest of the MCU. They'll get there - there's no way the Guardians don't show up in Avengers 3 - but for now Marvel is carving out a new niche, one that could spin off other movies going forward into Phase Three. I like this; while I was speculating that we might see Stephen Strange reacting to Peter Quill's quick moment of cosmic consciousness, or that Thanos would take note of another Infinity Stone on Earth, I'm glad that Guardians 2 is going to be playing in its own walled off corner... for the time being.
By the way, please note: Howard the Duck is wearing pants. This is apparently a Disney mandate.