Double standards are very prevalent among fans. Anyone who has been a member here for any length of time has seen it, even if they don't realize it. This is not to say that I'm not guilty of it myself. Even though I can't really think of anything right off the top of my head, I'm not so full of myself to think I'm guilt free. In fact, I would be willing to bet that everyone on this site has been guilty of it at one point or another. I just wanted to get that out of the way. Again, in no way do I mean to sound condescending, or like I think I'm better than anyone, but I fear that is how this article might sound without a little explanation before I get into the proverbial meat and potatoes.
There are many examples of double standards being used pertaining to countless CBMs. The two that I will focus on the most are the ones that are probably at the foremost of everyone's thoughts, as well as garnering the most attention on this site. Of course I'm talking about X-Men: First Class and The Avengers.

Many people have a lot of hate for First Class, and there are many reasons that have been given. I've seen arguments stating that people do not like that the original team is not the same team from the comics. Certain characters are making appearances that should not be there yet according to the comics, as well as certain things happening that should not be happening yet (like Beast getting blue fur). And of course my personal reason, which is the fact that the creators of First Class have admittedly decided to ignore certain things from the first three X-Films, while still calling this a genuine prequel. I will be comparing some of these arguments that we know from First Class with things that we know about The Avengers, as well as fan reactions to both. Generally, it seems like most people cannot wait for The Avengers, and seem to be completely okay with everything that has been heard thus far, while its the complete opposite for First Class. Lets dive in, shall we?
The original team from the comics will be changed in First Class. While this is true, I don't understand how people can be so completely irritated by this, but in the meantime it does not bother them when talking about The Avengers. The original team in The Avengers comics consisted of Iron Man, Ant Man, Wasp, Thor, and Hulk. From all accounts, the movie version will consist of Iron Man, Captain America, Thor, Hawkeye, and possibly Black Widow. (I left out the Hulk because whether or not he will be an actual part of the team in the movie is still up for debate.) Why all the hate for First Class when The Avengers changed the original line up as well? Essentially, both movies are guilty of changing the original team. So where is all the hate for Avengers?
How about the fact that the Cosmic Cube is rumored to be in The Avengers? Most fans seem fine with this, even though in the comics, The Cosmic Cube was created by A.I.M. and had nothing to do with the early incarnation/formation of The Avengers. This will most likely not be the case since there are no hints whatsoever that A.I.M. will be a part of any of these movies. Why is it that something so important in the movie can be changed from the comics and no one seems to have a problem with it, yet people pick apart every little changed detail in First Class, like Xavier walking, or not being bald?
Characters making appearances that should not be there yet according to the comics. This is something that a lot of fans complain about in the X-Films. In First Class, just about the entire team will consist of characters that did not come along until way later in the comics. Moira Mactaggart, The Hellfire Club, even Azazel are characters that should not be there according to the comics. Well guess what? The Avengers have Nick Fury, SHIELD and Black Widow who, according to the comics, should not be there yet. Also, both movies are forming the teams in different ways than the comics did as well.
So basically, what it comes down to is that fact that both movies have changed quite a bit of things, and in many instances, they've both changed very similar things. The amount of complaining for First Class far outweighs the complaining for The Avengers. Why is that? Is it because people just automatically hate anything attached to FOX? Is it a general lack of comic book knowledge, like maybe people know more about the X-Men's history than they do about The Avengers, which in turn means they don't recognize all the changes in The Avengers to get mad about? I truthfully do not know the answer, but the double standards are very clear to see. You would think that a quality movie would be enough to please people regardless of the changes made, but the history of CBMs has proven that wrong.
In any case, thank you for reading this lengthy editorial. I look forward to reading all of your opinions as this is something that has made me wonder for quite a while.
~CDB