doyle_sb4 and I have worked out why series 2 of DW was so giggly and fluffy at times; all the angst was being used up by Torchwood. Also, the TARDIS got a bit mixed up and gave Jack's flirtiness to Ten instead. Having said that, Jack did seem more like his DW self in the last episode.
So, the moral of this episode was: indefinite life is a bit crap, but being dead is worse. Oh, and Gwen is an idiot, but we knew that.