The introduction of Elaine?

I was just on the Series 5 page and it said that the person Arthur and Merlin save from execution is a woman and it got me thinking: could this woman be Elaine? In the legend, Elaine is the most infamous of Arthur's half-sisters the other two being (Anna) Morgause and Morgan (Morgana). There was also a picture of Angel (Gwen) walking with a woman in servant clothing. Could these two women be the same the person? Also, do you think that if this woman is Elaine that she would be any relation to Arthur and/or Morgana and/or Morgause? Post your thoughts here!