I've been collating a number of snippets from my various sources, and whilst some have been very accurate in the past, some have been way-off as well. Putting together all of the information that I've been given to date, I've decided to tentatively post this here in the Rumours section, and as such should be treated accordingly.
Who will you miss the most and why?
Death 1 - Charlie
No great shock to the majority of Lost Fans here as it's been a persistent rumour for a number of weeks. He apparently dies whilst performing a heroic deed saving another. It's been speculated that he drowns.
Death 2 - Sayid
This has been a floating around as well for a while but has not had the sort of weight behind it that the Charlie death rumours have had. The actor has been a little outspoken recently about the show and this has led to these rumours. My source tells me he is killed in the Season finale in the fight with The Others. I for one will miss Sayid the most.
Death 3 - Kate
This is the one that will cause the biggest shockwaves throughout the Lost community as it impacts both sets of "Shippers". I've heard that Kate is killed in friendly fire caused by Jack.