I am the original topic poster both here and on the apple support site. Please see the following links for reference:
https://forums.macrumors.com/threads/727453/
http://discussions.apple.com/thread.jspa?threadID=2049659
http://discussions.apple.com/thread.jspa?threadID=2042490
Here's a bit of what has happened in my situation so far. Had the original ST9500420ASG drive in my build-to-order June 09 MBP 15. It has the 0006SDM1 firmware in it. Had the click + beep + freeze from day one. This was prior to the 1.7 firmware update. Wondered what was going on, was hopeful for a fix in the 1.7 firmware update, but as we all knodw that did not happen.
I tried my hand at getting apple to do something, but they would only offer to replace the computer which at the time was not an option as I had just started my post doctorate educational program and downtime was not acceptible. They would not arrange to ship me a new hard drive at that time.
On recommendation of another poster, I opted to try the non-G drive ST9500420AS with enclosure from OWC and install it myself, thinking I would have a backup 500 GB drive and an enclosure as well. I installed it and everything worked flawlessly. The firmware on this drive was the 0002SDM1 (apparently older, but I don't know their naming convention)
In the meantime, my schools tech support people (my school is an authorized apple reseller, not sure if that matters) quickly got me a replacement G drive, also with the 0002SDM1 firmware on it.
I again swapped this drive in to see if it worked better. I did not hear any beeps, but there was an abnormal, yet different click from time to time. I did not notice any beach balls when using this drive.
Preferring the silent no-clicking of the non-g drive, I swapped it back in and decided to give that one a try for a while.
I used the non-G drive without trouble until yesterday, 8-9-09 at which point the system froze, mouse still working but otherwise unfunctional. Of note was the faint, but different than original, beep at an interval not unlike the busy signal on an american land phone line. I had to hold my ear up to the hard drive area under the keyboard to hear it well. Only option at this point was to hold down the power button and cross my fingers.
The machine did not boot up. Powering on the system led to the same faint beep - beep - beep sound.
I decided to put in the "newer" G drive with the 0002SDM1 firmware and have been using it since yesterday. So far its ok. But I have to admit I don't trust these things at all. This is the first computer of any kind that I've had so much trouble from the beginning with and it really is coming at a bad time for me. I'm in a post-doctoral specialty program that is very demanding and I'm probably going to pay for spending so much time writing this post but hopefully it helps someone. I don't have time to worry about my computer and its ability to let me get work done. I'm glad that prior to all this I had a very comprehensive and regular back-up plan in place and through it all I've lost an insignificant amount of data. I sincerely hope there is a firmware fix. If not in the short term, I may opt for a different brand of drive.
Of interest is the fact that in my program, all 6 residents were required to buy macbook pro's. Of the 6 of us, 2 of us ended up buying the June 09 15 Build-to-order with a 500 GB 7200 drive. The other guys drive is ok as far as I know. The others in the class bought before the new ones were out and I don't think any of them upgraded to the 7200 rpm drive.
Also of interest is that I have a BS and MS in computer science but it did not make me any more credible in posting this 1.5 months ago as a definate problem. Oh well. Its amazing that even with the traffic the apple support forum has received that this issue is just now coming to the surface of the bigger news sites. I tried to message Arn about this some time ago and got no response.
...and yes...before everyone chimes in with helpful hints...I have tried
1.) hdapm
2.) turning off the "turn off hard drives when not in use" option
3.) resetting NVRAM / PRAM
4.) SMC reset
None of these for me did anything. Smart Utility gave some useful information with regards to parking numbers, and before I swapped the original drive out I ran it and it was reporting drive failure. I'm scared to run it again on the replacement G drive with older firmware.