rchiu91,
Welcome to the forum.
I would suggest registering your television online. If you're in the U.S., that will give you an additional 3 months of warranty coverage. Once that's completed, call 800-SAMSUNG and set up a service to have your unit inspected.
Keep me posted.
--HDTech
I have seen similar threads, but nothing exact. I have a Samsung that is about 12 months old and just recently, I started noticing yellowish discoloring on the whites, the blacks are becoming grayish-blue. It does come and go. We checked the cables, tried to adjust the color, played a HDDVD on our PS3- nothing worked. It will stay for a couple of hours to days and then be gone for a day or two and come back. Any suggestions, thoughts? Is it something that is going to require maintenance/cost?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic