I returned my week 6 quad core iMac i5 a few days ago (slight yellow tinge, some dead pixels in iSight) and asked the Genius in the Apple store to give me an iMac that's newer than the week 6 I had just returned, possibly a week 7. He returned and I looked at the serial number on the bottom of the box and it looked like it said that it was a week 8. I was excited, so I took it home. But then I turned it on and checked and it said that it was a week 5. I am going to return my current week 5 iMac since it also the yellow tinge which is even more noticeable than the past week 6 model and there is a speck of dust under the screen (right in the middle). Does anyone know what the newest/most current week for the iMacs is at this time?