The basic question here is, what should we take as canon when discussing marvel comics?
The question arises because, to me the primary source for Marvel canon should be the closes source that we have to Marvel comics itself. As far as I can tell, that would be the comics themselves.. the reports occasionally released by Marvel Comics itself, and the content of Marvel comics website marvel.com/
@Comixfan has said that marvel.com isn't a good source. I believe the source is the best, because of it's accessibility and it's proximity to Marvel Comics. I hope Comixfan will find this thread and share some insights. I don't want to speak for other people.
As for taking the Comics themselves, I believe that presents it's own problems. If you take an example that people are currently using to "prove" that Squirrel Girl is no longer a mutant:
but what does this scene actually prove? In my opinion, it only shows that SG's mother enjoys telling a story about SG not being a mutant. even if such a story were to show up in more scenes, it could simply be the writer having fun with the spreading of rumors. To me, the things in the comics can only be taken as canon if they show up in multiple comics, over an extended period of time, and under multiple writers and editors. (I've never read anything with SG, so I'm not saying she hasn't been retconned.. only illustrating that people should try not to read too much into a single scene in a comic)
While I was considering this topic, I also came across a CNN story about Iceman being gay (the "all-new" version) and the story cited Bendis and issue 40 of the X-men. It's the issue that we've all read with Jean saying that Iceman is gay.. but Iceman never (in that scene) actually says he's gay.. in fact, he says he thinks Jean is using her telepathy to mess with him. Yet people use the scene to show that Iceman is gay, while completely ignoring the fact that the discussion is a result of Iceman saying that Magik is hot.. and Iceman had also told Cyc that Laura was more attractive than Jean. In this case, the comics actually don't support the narrative that CNN and Bendis are trying to tell. To my knowledge, the "all-new" Iceman in the comics has never acknowledged being gay and has no boyfriend. Does Bendis or CNN saying that Iceman is gay actually make it so, even if the comics make it appear differently?
Anyway, that's some thoughts to get the discussion started. Really what I'd like to know is, what source do you use when determining Marvel Canon and why do you think it's good? Do you see any problems with that source?