Same issue here, just bought my MBP 2 weeks ago. Bumping this thread in attempts to keep this thread alive. I brought this to the genius bar and they insisted it was normal behavior. After I spent a few minutes convincing them that its not the HD, and they should listen to the sound, they went to the back and came back after about 15 mins.
They then told me that my opitcal drive has a loose arm, and it is normal still. I had to talk to a manager at the store to have the optical drive replaced. Another 30 mins of them trying to convince me to deal with the sound and that it is normal. I asked them to go ahead and bring me any of their 15" mbp demo laptops and show me that several of them have this sound. They didn't want to entertain my request.
I was at the genius bar for 1.5 hrs. Everyone looked at at me like if I was being too nit picky. It isn't just 1 tick that comes in every hour. On a bad session, it's a repetitive rapid motion tick. What was probably worse was their manager insisting that it is the HD, after 2 of their 'geniuses' had openly agreed that it was the loose arm in the optical drive.
I now have my mbp back with a new optical drive, still have the ticking sound, and they have accomplished their goal of making me deal with this sound on a machine that I paid $2500+ for.
On second thought, is it possible to return this? This was my first macbook purchase, and I am just going to go back to a windows PC. I went with a mbp because the machine felt more stable, solid and heard a lot of good about their customer service, guess it is no different than a $1k windows laptop from Dell.
