http://spoilerslost.blogspot.com/2009/0 ... uture.html
THIS MIGHT BE CONSIDERED A SPOILER. I THINK IT CLEARS A LOT OF THINGS UP.
THIS WAS A SHORT INTERVIEW WITH TERRY O'QUINN AT A GOLF CHARITY EVENT. HE ANSWERS THE QUESTION ABOUT HIS CHARACTER IN SEASON 5 AND QUESSES WHAT MIGHT BE IN SEASON 6 (FOR HIS CHARACTER). HE DOES NOT KNOW WHAT WILL BE IN STORE IN SEASON 6 FOR HIS CHARACTER.
I got this article from Dark UFO site.
Spoiler
So i guess as of now Locke is really dead. Dead is Dead on Lost