Flash memory is actually pretty slow, although the seek times are of course almost instant.
Transfer rate however is not that great. And I cant see DRAM based drives ever catching the raw storage of magnetic media.
But in terms of product life cycles old fashion hard disks are in the maturity stage there not going to double there performance over the next year and a half like graphics cards do. Where as flash drives are still in the infancy stage, there is plenty more to come from flash drives.
But they have a long way to go to overtake conventional hard disks.
Seagate plan 1.5TB by the end of 2007, transfer rates will surely rise significantly with this due to the higher data density. Hard disks are extremely reliable no matter how many read/write cycles they go through.
Flash is *ALOT* slower in terms of transfer rates than normal hard disks, has limited read/write cycles before dieing, and lets not forget that while some of these may narrow, HDDs *are* a moving target. I couldnt cope with an 80GB drive as a C: drive, even with other magnetic drives for storage. When Vista comes out and chews 10GB+ of my hard disk, this will be even worse.
DRAM based drives I can see one day becoming more mainstream, but not Flash.