For the past two seasons, Damon and Carlton made it a tradition to name Lost's finale episode after a Jewish-bread product. This season's finale was originally going to be named "The Matzoth." However, the producers decided to end the tradition and are naming it, “Snake in the Mailbox.” Carlton and Damon are not saying that the finale will be scary; they are just saying that the end will be so shocking that the best way to describe it would be analogous to find out that we have a snake in our mailbox. They also hinted that "Desmond and Penny's relationship will be a part the season finale."

Damon and Carlton also hinted that the Jack, Sawyer, Kate triangle is not over. Kate chose Sawyer while at the Hydra, which was the right choice for that moment.

When asked whether the Jacket (Juliet-Jack) relationship would blossom, they just hinted that they are watching their chemistry and see how it will work out. There is still a lot to learn about Juliet. Is she good; is she evil, what is her reason for being on the island, what is her motive or agenda? They did say that “her relationship with [Jack] is something that is going to be really compelling as we run into the later part of the season."

Source: ASK Ausellio