The new Mt.Rainier standard is currently making it's way to CD-RW hardware and software. It is pushed by major players like Microsoft, Philips, Sony & Compaq. Our partners at the CDFreaks have done a nice job explaining this new format - worth a good look.
The idea with the Mt. Rainier format is to enable native operating system (OS) support of CD-RW drives and background formatting. This will ensure greater compatibility, eliminate users' dependence on proprietary read drivers, and make the technology easier to use.