I just got my S360 2 days ago and I must say that I disagree w/ everyone else regarding the fan.
I'm not a silence freak, but the fan is starting to get annoying. I don't know if this problem is isolated to a few S's but mine is one of them. I installed Mobile Meter
, and I notice that the fan turns on at > 40 deg C. It has a slight whine which is annoying and I can clearly hear it when I'm near it, even with a tv on in the background. The fan speed gradually ramps up when above 42 deg C, and it gets really loud above 50 deg C, almost as loud as the optical drive when reading/writing.
All the above is w/ the CPU power management set to adaptive (usually running at 600 MHz) and the fan setting on 1/Quiet. I don't think the fan should come on at all when doing light tasks and websurfing, especially when the CPU is at 600 MHz and the temperature inside my house is 65 deg F.
I just wish Sony would redo the fan settings, shifting everything up 10-15 deg C so I wouldn't hear the fan 95% of the time. The CPU has a thermal spec of up to 100 deg C and Sony is keeping it cooler than a watercooled P4.
I too was thinking of getting a 7200 rpm hdd, but after playing around on the standard 80gb with 8mb cache, a faster Hitachi is no longer appealing. Plus, I can use the extra 20 gigs more than the extra 3000 rpm and possible lack of warranty.
My 2 cents. If anyone w/ an S would like to dl mobile meter and post when their fan turns on, please do