I agree with lizard2112 on the fact smoky is taking on the apperance of all of the illusions that have been seen.. The only reason the others let michael & walt go in my opinions is that they never plan on them getting very far... I think they just let them go to get micheal do what they wanted knowing thy really would end up back on the island

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Please don't give up, Des. Because all we really need to survive is one person who truly loves us. And you have her. I will wait for
you. Always. I love you, Pen

DESMOND: I love you, Penny. I've always loved you. I'm so sorry. I love you!
PENNY: I love you too.
DESMOND: I don't know where I am, but--
PENNY: I'll find you, Des--
DESMOND: --I promise--
PENNY: --no matter what--
DESMOND: --I'll come back to you--
PENNY: --I won't give up--
BOTH: I promise. I love you.