PSPCasting
ChipGuy writes "Om Malik points out the launch of Sony PSP in US could actually turn Sony's fortunes around and thinks that new unqiue applications like Sajeeth Cherian's latest software, PSP Video 9, might be the real reason. Cherian created Videora bit torrent client's new hack, PSP Video 9. It takes any video and turns it into a format that PSP can read. So now you can download videos using Videora, and then convert them to PSP friendly format within a few seconds.He calls this PSP casting."
I'm not sure what you mean by "proprietary" in this case, as the PSP uses MPEG-4, which is No more proprietary than MPEG-2, your counter-example.
You put everything on a Memory Stick Duo. Theres no way to write disks for it (yet?)
It uses a MPEG4 format for the videos too, its not some crazy proprietary format just a slightly modified version of mpeg4 IIRC. Makes it easy to transcode. This is why theres already so many converters to toss video onto PSPs