Since the resurrection back in 05 we've had 9 and 10 consumed with guilt, getting all maudlin about the Timelords demise and his actions in causing it.

We've now found out that the reason Dr 8 caused the annihilation of Daleks and Timelords alike was because the Timelords were about to initiate a force that would have caused Universal genocide, and in doing so become every bit as bad as the Daleks.

The events depicted in The end of time must surely have reminded the Doctor that what he did to end the time war, possessing the moment, was the most logical course of action. The needs of the many outweighing the needs of the few and all that.

His actions, and the actions of the Master is justification that the Doctors original actions were correct, the Timelords corruption had become absolute and must be ended.

I think 11 must not be burdened with the same guilt as what 9 and 10 burdened themselves with and work toward ensuring that nothing like that can happen again.

Yehhhh I agree, more fun and carefree. Though maybe the S5 ending will have something that causes the Doc to go moody again in S6 and develop

Oh shush, that was the only missing line from his dying Spock routine in the radiation chamber

I completely agree. I guess he probably hurt from the various innocents involved in the whole thing - but at this stage and given how quickly he gets over other things it's probably time to move on.

That surely, was the whole point of tonights episode? The Doctor doesn't have that burdon anymore now, and even The Master knows the truth. So Doc 11 can have a carefree existance.