It appears that they answer is... "yeah, kind of". Insight was gathered from application details on one of the applications ("telekinisis" aka "iPhone Remote") created at iPhoneDevCamp.
MediaStreaming - telekinesis - Google Code: "Streaming video and audio
If you store movie or music files on your computer, you can watch and listen to them on your iPhone using telekinesis after enabling the feature in the preference pane. This feature is off by default for security reasons, please see below.
The files you play have to be supported by the iPhone:
* H.264 Baseline Profile Level 3.0 video, up to 640 x 480 at 30 fps.
* MPEG-4 Part 2 video (Simple Profile)
* AAC-LC audio, up to 48 kHz
* .mov, .mp4, .m4v, .3gp file formats
* Any movies or audio files that can play on an iPod.
Over EDGE you stream media in real time up to 160kbits (in practice 80-100 however.)
To play a media file, simply touch it in the file browser mode. The CoreMedia (Quicktime plugin) player will launch and start to buffer the media. You can use other applications (Mail, Phone, etc) while the media is playing but you cannot navigate to other MobileSafari pages.
As of now there is no way to stream playlists or queue multiple files.
Caveats of media streaming
The iPhone doesn't appear to accept media encrypted with a self signed certificate. To enable streaming, iPhone Remote needs to send it insecurely.
If you choose to enable this feature, anyone can connect to your machine to access m4b, m4v, m4a, mov, and mp3 files if they can access your computer and know the full path to the file
Do not enable this unless you are sure your network is secure.
You can enable this feature in the preference pane. Hit "Restart Server" after checking the box.
This application (still alpha) sounds very promising to me although I will certaily wait until it is at least Beta (and I actually have an iPhone). Any of you out there that already have one want to give it a try and let me know how it works?