Hmmm....canon.
Well, it's easy for me. Aired = canon. That is the technical definition if one insists upon a definition and I suspect more don't give a damn than do give a damn about what is and what isn't canon.
However, to be honest, the technical definition doesn't matter any more than it matters what I think of Kira/Odo as opposed to what someone else things. It's all make-believe, made to sell soap or whatever they sold back in the late 1960s. The trick is to reel us in and make us care so we'll watch more and especially stay tuned to those commercials and go out and buy shit we don't need.
As for me, while I could name a few shows that aired that are technically canon, I have mentally booted them out of my personal canon.
Same goes for books. Even though technically they are non-canon, if I like a Star Trek book, it's canon.
Very simple, no hassle. I don't argue with people about canon. Why? I just don't care. At the end of the day, I either like a Trek episode/movie/book, or I don't. If I like it, I consider it canon. If I don't, I don't. If others have different definitions or system, whatever works for them works for me. If they want to feel they're right and I'm wrong, at the end of the day, it doesn't matter.
Because I'll define canon any way I want if I care to think about it (and most times, I don't. I just enjoy or dislike the shows/books.) And so will you.
At the end of the day, it's just a TV show/movie/book. No matter how great (or sucky!) one is, that's all it is. To fight over what is legitimate and what is not legitimate is just daft.
In the words of Mr. Hammy, "Get a life!"