I've had my 27 inch iMac since November 09, it' has the 1TB hard drive which makes that annoying grumbling stomach noise which seems to be getting worse over time. It also has the yellow tinge problem although not as bad as some that I have read about. What are the chances Apple would replace the machine 6 months out? I would order the 2TB HD just because I do not want to go through the hassle of possibly getting another 1 TB drive with the same problem. Now that I've read posts from some that have had multiple replacements I'm sorry I just kept this machine without trying to get it replaced.