I'll say it again, embedded 'media extender' functionality seems a little less necessary when you have open access to the network and the internet. To illustrate, have a look at all the ways you can stream music to your PSP from your PC, even though the PSP OS doesn't have "media extender" capability on its official checklist. The avenue of choice for this currently is using RSS feeds, and freely available server software on the PC side.
Open web access is a great enabler.