When Anders blew up the chantry it felt like a punch in the gut.  My jaw dropped and I was disgusted and disappointed.  This character I've been working with nearly the entire game does something that in my opinion is terrible.  I invested time and  emotion in this character.  I felt betrayed and was ticked off for a good day basically feeling that what happened had ruined the game for me.  Then I realized that the game had got a genuine emotion out of me that really stirred me.  Regardless of if I agreed with what happened or not it definitely had a deep emotional impact on me.  One that I will be feeling for a long time.  Bravo Bioware on making me feel for this world and these characters.

 The ending managed to, in the stretch of fifteen minutes, make me hate Anders so much that my hands were shaking when I made my choice about his fate. It made me hate every living mage out there for relying on me to pull them out of the shit but then force me to fight them when they go emo and turned into abominations.  Even when I defended them like the dumbass I was! The only mage I don't hate right now is Bethany but given how shit went down the drain in the end, I'm not sure she'll be around much when I roll my thundering hate over mages in the future.
 
I guess bravo on Bioware for managing to dig out such burning rage in me. 

That shows true emotion through a narrative. From a game standpoint it sucks since you built up a relationship with a character through two games, is fairly likable and extremely useful to the party as the sole healer, and pretty much necessary for support in the higher levels of the game. But from a story standpoint....you need to make a tough choice that could totally change all of your decisions in the endgame and the perception of the worlds storyline.  It was really a great character moment that would make you think.

I for one hope Bioware continues having character moments that make you think in future games.  When playing Mass Effect 2 I felt some strain on Mordin's sidequest but nothing to this level.  What I think was even more painful about the situation with Anders was the fact that I helped him do it without knowing.  I did all of his sidequests.  That heaped more betrayal on top of it all.  Not only did my friend commit an atrocious act but he fooled me into helping him.

When Anders blew up the Chantry I felt like I had been punched in the gut, because it was a completely bullshit plot point that comes out of nowhere as a convenient deus ex machina to hastily bring about the conclusion of the game. 
 
It's also a completely nonsensical action for Anders to take, because if he wanted to start a war with the templars, and had the power to essentially vaporize buildings, why not destroy the Templar Keep?  Why obliterate hundreds of innocent lives, including many mages?  Why allow Meredith to invoke the Rite of Annulment, which led to even more mage deaths? 
 
It made no sense.  Sure, it's shocking, and throws the moral compass out of whack, but it's a stupid plot point.  There are better ways to add shocking complexity to interactions with your party members. 
 
And furthermore, why sit and sulk about how conflicted you are after you've done it?  You'd think someone would require more internal certitude to essentially murder innocent people. 
 
- Scott

Anders is an idiot and I feel stupid for siding with him in my first play through. This time around, I've sided with the Templar.

I believe he blew up the Chantry because the chantry is the reason why templars exist at all.  The church wasn't doing anything to stop the oppression and the religion was the reason the mages were imprisoned.  Also he wouldn't have been able to access any templar buildings even if he wanted to.

Dude my Hawke was dating Anders! I was so hurt that I never wanted to see him again, but at the same time because of everything that happened before I couldn't kill him. So I told him to leave. I still sided with the mages. What was happening to them was wrong, plus siding with the templars meant committing genocide, which I'm not cool with.

My Hawke had fallen in love with Anders and had him move in with her.  So when he blew up the chantry I was also extremely furious and felt completely betrayed.  But I spared his life and actually let him come with me to defend the mages.  The whole thing kept me thinking for a long time and what I would do if someone I loved did something like that.  For emotional effect it is great but only if you really invested time into Anders at all.  If you didn't then it is kind of a "wtf dude?!" moment. 
 
Anders does say that he blew up the chantry to force the mages and templars to fight it out.  So that they couldn't talk it out or the chantry couldn't resolve the issue since the chantry runs the show and controls the templars which control the mages.  You could also say that Justice/vengeance was clouding is judgement.

Yea, the game got emotions out of me as well. Sadly they weren't the good kind... I like happily ever after endings.

I don't feel okay giving Bioware credit for telling me my choices matter for a whole game then going "but not really". The contempt I felt wasn't their intellectual planned reaction, it was me being pissed off at a macguffin. I didn't find it an impressive array of intentional manipulation that at the end of the day, I can do whatever I want for 99% of the game then just decide in the last 20 minutes to help one group or the other. Meredeth is a hardass the whole game yet you can side with her even after your companion commits a terrorist act. Orsino breaks character on the drop of a dime as well, after siding with him. Fucking lazy, kind of insulting. Reeks of "we have a deadline". I don't enable corner cutting, when games give a shit they should get a pat on the back. If I ignore when devs don't give a shit, I'm telling them they don't have to try, I'll swallow whatever they give.

I like aspects of the game's ending, but I agree with Ryanwho that it reeks of corner cutting.  With proper time to develop the ending they could have enabled you to make more meaningful choices.  As it is, the game seems to play out the same way no matter what you decide and they just shoe horn everything with some spotty dialogue.  All logic seems to go straight out the window when you have to fight all of these demons while you're fighting the templars.  Where the hell did the demons come from?  Why are they fighting with the templars?  Are we supposed to be believe that this is all to do with the sword?  Or the infiltration of the templars that is set up earlier?  None of it really makes sense to me and it feels like they simply felt they needed more variety in the enemies but didn't have time to actually invent new ones.  Pretty sad.

As someone who never really liked anders it gave me great joy to stick that knife in his back.  :3

Agreed. I literally shouted at my computer screen "ANDERS! WHAT HAVE YOU DONE?!!?" Was it a perfect plan? No, but Anders wasn't exactly the most stable individual to begin with, so his plan probably wasn't all that well thought out. He was a desperate man acting out of desperation.