I think that she covers up her tattoo - I have tried to pay attention to see if it can be seen.
The letter that she read was from the guy that was killed in the pool house. He had slipped her a note when he tripped into her at the flashback party.
I too caught that about Emily's mother. I assume she could come back too.
Also - I have had the feeling that David isn't really dead for a long time. Nolan has an awful large amount of money and I can see him getting him out and into hiding to protect him. He is very instrumental in leading her into her quest to seek answers and revenge!!!
Also - Jack's girl friend - she was an interesting character that was thrown in - I am sure she will be shown more as well.
I also was taken back a bit when Victoria said that the house was the only thing she had left of David - she knows that her daughter is his too. Unless she is in complete denial!!
such a great episode - I watched it again!!! oh so good!