I believe the person in the closed casket in last year's finale is Michael (I know alot of people feel that way.) Here's why....

We already know Episode 8 is about Michael and we have been told we are going to learn who was in the coffin this season.

So, I'm thinking that in Episode 7 Michael will make an appearance at the end of the show, leading us up to Episode 8 about him. The flash forward will show either his death or his funeral and link it to Jack's flash forward from last year.

I also think that Michael's return to LOST is gonna be short lived.

We'll see what happens...