It's not all about fast boot times, really 10ks don't help "that" much in boot time.....
How about people that can afford them for business, live recording and such, backup servers for people that don't want to fork money for scsi.
Data throughput hardly is higher than with 7200 RPM disks. So I'm not sure how live recording, be it video or audio, will see any gain. What exactly do you call a backup server? If you mean data, it's more cost efficient to just have a RAID 1/5 array of large 7200RPM disks. The Raptors offer no value there.
Access times are really the key factor with Raptors, which helps with a boot disks. Which doesn't translate into just boot times.
Cost difference for the build from a 80gb drive to a 320gb drive is next to nothing, you pay a lot of extra money for a little more money they put into it, now obviously there are lines there where the cost to build goes way up also.
Yes, that's because 80GB is ancient and hardly produced anymore, if at all. Besides, you can't compare normal desktop drives to enterprise class drives or in this case the Raptors which fill a gap in between. Specially not price wise.
But all in all considering that hard drives in everyday machines are 400-500-600gb these days..
Standard desktop drives again, yes.
I could see something a little smaller, maybe a 250/200, but I doubt we will see a 36/74 and probably not a 150. We will have to wait and see though.
From 300 to 250/200, how would the platters be configured then? three 100GB platters? Doubt it. Either way 250 is impossible unless there is another platter size used, which would be rather pointless.