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The Seagate Momentus 7200.4 that doesn't have the built-in motion sensor.
(ST9500420AS). The model that ends with "ASG" is the one that is prone to the clicking/beeping/excessive head parking issues.

Question, does Apple ship macbooks now with the 0AS models? I just got a brand new macbook, beeps/clicks it's ASG. :(
 
I've run a 320GB 7200rpm Hitachi 7K320 in my uMBP 13 since I got it 2 weeks ago, and it's quiet as can be. Definitely quieter than it was in my Acer Extensa, which now houses the 160GB Fujitsu that came in the MBP. It's running at a nice and cool 36°C, and I've never seen it over 38°C in the MBP, where 45-50°C was the norm in the plastic bodied Acer. The single-platter Fujitsu now has a nice home in the Extensa. One of these days I'll get around to trying my WD Scorpio Blue WD5000BEVT in it. It's currently in an external enclosure as my portable backup drive.
 
Yes, they are shipping both drives. (They don't seem to listen to their customers complaints very well.)
So it is completely up to chance which model you get the AS or ASG, and this goes for both the 320GB and 500GB. I took the chance and it didn't work out.
1 out of the 3 computer I got was AS but had bad RAM
2 out of 3 had the ASG and beeped

I finally switched to the 5400RPM drive for my fourth MBP that arrives tomorrow. Hopefully, this one will have no problems. I am not pleased about getting a 5400RPM drive but would rather have a working computer.
Plus, I saved $50 by downgrading, and for $130 you can upgrade to the AS hard drive yourself. So for $80 you could get the correct drive and no beeping, plus a nice little external drive. (I might actually do this.)
 
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