Hi folks, just some speculative information....
I posted a wee while ago after recieving an email from CyberDrive support. CyberDrive was telling me that they'll add Mt Rainier support for my drive in mid-August, they also said that's when Windows XP will support Mt Rainier!
we will provide a MT Rainier firmware for CW058 in August time frame. That
will be the time, when Windows XP will also support MT Rainier.
Your support team
Thanks to burnproof for pointing out that this could be a fairly significant thing, which I'm sure hasn't been announced (or leaked) by Microsoft.
Given the amount of trouble XP has had with it's IMAPI service, it would hardly be surprising that Microsoft is looking to offer a better solution. But of course, it could just be read-only support. Anyone want to speculate further?