I dont think they well, at least not any time soon.
its all about economics.
if they (maxtor ibm wd etc) release 10,000rpm drives, then they will cut into their own scsi drive market share. So they will probably wait till the majority of scsi drives are comming out as 15,000 rpm before moving up with IDE.
This behavior must not continue! Feel the BURNING STARE of my HAMSTER... and change your ways!