Logic, dude.
Her Viper was destroyed. It was an old Mark-2, so the Cylons were bound to have a few themselves. If not, they could easily have the design schematics to be able to re-create one in perfect, seemingly authentic detail, just as a new pre-programmed Kara Thrace could have been manufactured, placed in that cockpit and sent on her merry way. Also consider that Vipers have not been seen with FTL drives, so it's logical to assume that she had a helping hand from something, possibly a base ship or something otherwise unknown. Whatever it was, it would have had to jump into the combat with the rest of the Cylon fleet, possibly hidden elsewhere, to 'drop off' Kara. Upon being dropped off, her programming would re-initialize and -poof-, she re-awakens not knowing HOW she got to earth and back... how da*n convenient, huh? Also notice how her hair looks a lot longer? ;) I'd bet that's how she's manufactured.
I don't think the President will die. Not only is it uber early in the season for that to happen, but... it just seems unlikely they'd kill her off at this stage, especially with her playing such an important role in the story.
Just my thoughts and theories.
~Aeries.
