I liked Guinan and I like Whoopie. But, I was not impressed with the writing for her character in Yesterday's Enterprise nor Time's Arrow - both were cheap, and unnecessary. Time's Arrow was a total cop-out. An attempt to answer "a burning question" (really? who cares) and fell short - much like Jack's tattoo on Lost. Did anyone serious think "if this series ends without explaining that tattoo, I'm going to be very upset"? I would rather have gone to my grave with my own imaginings of how Picard and Guinan met than been subjected to that simplistic throw-away sub-plot.