His frustration is understandable, and I'm certainly guilty of venting at times too (after wrestling with one, or likely more, browsers!). But the fact that it is understandable doesn't mean the title of the post is any less nonsense. In my opinion the Microsoft employee is justified to point this out.
He would be fully justified if he calmly pointed it out, explained that the headline was sensationalistic and inaccurate and left it at that. Instead, he loses focus as he goes further, turning the reply into a flame:
"Meanwhile, I'll take my Posteri over to Tumblr. Maybe they have more maturity when it comes to handling the occasional bug."
That's not a constructive way to handle criticism. There was a great opportunity to take the high road here, but he ends up just tossing flames back and the whole experience becomes a net-zero shouting match. Neither of the participants in that exchange have the high moral ground here.
