BDP-83 UPnP/DLNA Media Streaming FAQ
Can this player stream digital media from network sources?
Yes, as of official firmware released January 5th, 2010. 
This feature is currently experimental This feature can be accessed from the "My Network" icon in the "Home Menu" screen. It requires a DLNA-capable media server running on your computer. The supported media types are the common set of what the player can decode and what the media server can stream.
What formats are supported?
Different formats are available for media streaming than playback from USB devices. They currently are:
jpg mkv mp3 mpg png vob
For more details, there is a topic of "What are the supported media file types?" in the middle of this BDP-83 Wiki page: BDP-83 Media Files FAQ, each table contains a column named "DLNA playback?", which lists these supported media types as well as any specification limits. However, please also make sure your DLNA server can also support the specific media type before adding them to the shared folder/file list.
Do any DLNA media servers offer working transcoding?
Most media servers will serve up video which is supported by Oppo's DLNA implementation. Other formats require transcoding. For example, TVersity can be configured to stream compatible formats and transcoding unsupported video to MPEG video/MP3 audio.Install TVersity and the supplied codec pack.
Overwrite your "profiles.xml" found in "C:\Program Files\TVersity\Media Server" with this file: [File:http://dizzysound.net/media/profiles.xml]
Then restart the server.