I actually liked what they did with Will's character. In the past, Will has been a wavering, mousy character, even more so in many ways than Emma. He flounders in the direction he wants to take the Glee Club (seeing the Juvey Girls, he's completely thrown). He lets Terri manipulate him at every turn. Sue has little trouble pushing his buttons, and I've almost always felt she has the upper hand in her dealings with him.
I didn't know how they would have him react to the news, but this is, after all, a central plot point for the series, and a defining moment for where they take this character. I think most of us probably felt his reaction was shocking, but it felt "right" to me, in the sense that this is the Will I've wanted to see emerge. I doubt we've seen the complete end of the mousy Will, but his sense of direction should be clearer because of the confrontations. Now that he's been stripped of what he was most passionate about (his marriage and the Glee Club), he may become a stronger man on the road back.
Then again, this is Glee. Who the hell knows where they'll go with it?