I have one primary media room for audio and video, and I enjoy the functionality you described:
1. audiophile stereo listening
I currently have an HP Media PC w/M-Audio Revolution sound card in a closet behind my screen connected to my pre/pro running Foobar2000 and Meedio using ASIO. i can control it from my wireless KB and HT screen or notebook w/remote desktop.
2. cD player and surround sound music
i use my Denon 2900 for CD, SACD and DVD-A
3. netflix and internet video streaming (abc.com, hulu, etc.)
I use my xbox360
4. Movies (BD & DVD)
I use my pS3 for BD and DVD, xbox for HD-DVD. I could also use my Denon 2900 and HP Media PC
5. video from computer stored on hd
i use my HP Media Pc for home video
6. HD DVR
I use my Time Warner Cable rented motorola HD tuner/DVR box The dual tuner/DVR box is $15/mo. I would be interested in alternative DVR soludions as long as they are HD.
7. Web browsing
I mostly use my laptop while listening to music from my HT system, but sometimes i will browse on the HT screen using wireless Kb/Ms
Technically I have the following interests:
a. I have a component display (RPTV) and component pre/pro and too many component inputs. I plan to upgrade to front projection HDMI and HDMI pre/pro so any future video sources should use HDMI
b. For audio I would like my audio server to sound better and have assumed I will need to get an external DAC and perhaps even a tube 2-channel pre-amp. I can see how an audio server would easily connect with HDMI to a pre/pro but how would it connect to a DAC or 2-channel pre-amp?