Oh, let's see what I can remember...
Pretty sure her powers were pretty much standard Psi. (Both Primal and Praetorian.)
Daughter of Wu Yin in both realities. Wu ran the grocery store Penny stood outside in Faultline on Primal Earth. Wu was the head of the Syndicate and Yin Corp. on Praetorian Earth.
Although never revealed on Primal Earth, Praetorian Penny's mother (and Wu's ex-wife) was Vanessa DeVore.
The Clockwork King was obsessed with young Penny and considered her his queen. She proves to be a calming influence on him and there are signs in her story arc that she might be able to rehabilitate him (partially, anyway.)
In Praetoria, Metronome (Clockwork King's counterpart) was working with the Syndicate to free Penny from the psychic network. (
http://paragonwiki.com/wiki/Penelope_Yin_%28Praetorian%29) Wu, however, wanted her freed for the purpose of controlling the rest of the psychics. (
http://paragonwiki.com/wiki/Mr._G_%28Primal_Earth%29)
Can't recall too much more at the moment. A bit rusty with the passage of time, and all.