Ok I see your train of thought. His first post was just about it being a PS blog but people leave out motivating factors all the time in their posts and clarify their stances afterwards. I'm willing to err on the side that his statement could be made at anytime before the preview came out and after the game launched.
I can see why Jason's remarks come across as petty sniping considering his job but there were a ton of buzz kills in the announcement threads decrying Activision's involvement. Do they all have bad timing?
I'm approaching this more from an irrational level (as I think most people are being irrational). You know how sometimes a "mood" can be ruined, or people can get pissy over something. Basically, I see it like this:
People are really hyped for this game (they love Avatar + Platinum. It's a dream come true). First preview is out, people are really happy it sounds good. Jason bluntly says: it's a Sony preview, do you REALLY think they wouldn't make it sound good. Then after that other sites start releasing previews and they are also positive.
So following that timeline, I can see why some would think Jason was just kind of trying to be a buzzkill. The other previews reinforce this (at least to them). Again, Jason was NOT wrong to make his post (there is nothing wrong with him being skeptical). And most of the anger towards him is not rational. Well, i don't want to write off every post. I guess there is a debate to be had about whether Sony blogs are legitimate previews or not (in terms of bias). But generally, I think most people that are mad were mad because of emotion and not what he said.
Just my 2 cents. I don't mean to offend anyone. Trust me, I'm a huge avatar fan (obviously). I love Platinum. And yes, the Sony preview got me excited. But I see nothing wrong with Jason being skeptical of a Sony preview (or previews in general). Whatever.