Ultimate Jenna Theory - Revision 1

This is basically a theory that's been floating around on the internet for a while, but is now confirmed by The Snowmen.

What we know:

• Oswin and Clara have the same physical appearance and voice
• They are around the same age
• They both had the same last words, said to the Doctor, "run you clever boy, and remember"
• They both (seemingly) had the same name, Clara Oswin Oswald
• They both died shortly after meeting the Doctor
• Christmas Special Clara and spring series Clara are both governesses (filming spoiler confirmed by multiple blogs)

In the theory, Clara is somehow splintered through time, like Scaroth in the Tom Baker episode, City of Death (available on Netflix if you want to reference it). Scaroth was splintered in time due to an accident on a spaceship. What's unclear is if Clara was splintered sometime during her lifetime, or if all of her incarnations were born separately. Neither of her incarnations that we've seen so far appear to be aware of the others, unlike Scaroth, who would slip into unconsciousness and wake up in another splinter of himself. Also if she was splintered during her lifetime, where/when is the original and have we met her already/will we ever?

<speculation>
I like the theory that Clara is Captain Jack's daughter. Perhaps some of the time energy that caused him to be a fixed point in time and space went into her, and she's slightly less fixed. Any time she dies, another version of her crops up somewhere else in history. Time then proceeds to rewrite so that new version has its own life and memories. Both her and Jack can be killed, but they won't stay dead for long. Jack comes back as his own self in his own body, but due to the time energy being more diluted in Clara, she comes back at a random point in human history with a new past.
This might also be the work of the White Guardian. He appeared to have influence in The End of Time, transporting the Doctor's mom in and out of the time lock so she could save his life. The White Guardian needs the Doctor to survive until a certain point in his future, so he intervened to save the Doctor there. The White Guardian created Oswin to save the Doctor at the Asylum. When the Doctor became a recluse after the events of The Angels Take Manhattan, the White Guardian needed the Doctor to keep going as he was before, so he created a different version of Oswin to motivate the Doctor to continue to travel the universe. He knew the Doctor would notice the similarities and go off to find another version of her. The White Guardian basically used Clara to keep the Doctor on track to a certain point in his future.
The previous theory also integrates nicely with the whole thing with The Question. Perhaps the thing that the Doctor's name unleashes is only bad in the eyes of the Silence and the Doctor and is actually needed by the universe. Alternately, maybe it is something terrible and evil and Clara was created by the Black Guardian instead of the White. The Black Guardian would want the Doctor to unleash whatever terrible thing his name unleashes.
</speculation>

Whatever the explanation, we're probably not going to get much further information until episode 7 airs in April. We might get a tiny glimmer of information in any new trailers they release, but those probably won't come out until February at the earliest, more likely March.