Having followed this subject here and elsewhere, I feel a little bit the same a lot of options that are close, but no real killer or complete solution at a reasonable price. Lets break this down and look at the four basic components of a file based solution individually;
File Storage
File Access
Human Interface
File Transport
The first two are pretty much taking care of themselves on price point and simplicity I suspect. Since all the file storage and access has to do is give the transport device access to the file, a home network seems to be the most cost-efficient and flexible solution to me. A simple router is $100 and a NAS can be put together for anywhere from $300 to $3,000 depending on features and space (I have 500 GB for about $320). This approach means you can customize it to your specific needs (i.e. redundant RAID array, wired vs. WiFi, expansion architecture, etc) and do it within your budget. A localized media server (i.e. Nevo, Xbox, Mac Mini) will be popular with some people because its a simple all-in-one solution, but it limits your flexibility a little and puts a noisy, power hungry device in your listening area. Most of these options allow you to add external storage as necessary (usually USB drives).
Human interface is mostly about preference. I personally love the Sonos interface because I don't have to turn on a computer or TV to listen to music (everything comes across from the NAS or Internet via my home network). Some people like the idea of using iTunes on a computer to build playlists, while others like using a remote with their TV. Its a relatively simple task that can be accomplished in a variety of ways its up to the user to decide what method they like best. In the near future, I suspect we will get options that are more flexible (i.e. iTunes control AND/OR hand held device AND/OR a TV interface). As an analogy, think of how many different phones can access a wireless phone network. One person just needs a basic phone, but the next person wants a BlackBerry, while still another cant live without the coolness of an iPhone. Multiple devices/approaches managing the same task.
This leaves us with the transport, which is the area we are falling short right now. I think this is in no small part because it is by far the most expensive component to make improvements on ($1,000 mods to a Sonos or squeezebox device - yikes). It also presents these vendors with the least profit margin and hence little motivation to improve it. For every audiophile who wants uncompressed FLAC, there are 20 casual users who are fine with 192k mp3.
So what is the answer? I doubt well get acceptable solutions from vendors like Squeezebox or Sonos themselves since we are not the focus of their market. Rather, I think it will/should come from those vendors who are focused on us. Whats stopping Benchmark or Wavelength or PS Audio from developing a DAC that instead of just having USB or other digital input is actually a network device as well? Turn on your DAC unit and your Sonos network recognizes it as a zone player device and you are off.
If its true that the primary noise/jitter/coloration problems with file based audio mostly occur during the transport process of converting the file and moving it to the DAC unit, why not eliminate that problem spot? I think the Wavelength asynchronous USB DAC goes a good portion of the way to eliminate some of those problems (the DAC controls the data flow instead of the computer), but you still need a computer. What if the software to create playlists and decode the file resided on the DAC and you interfaced with it through a wireless device or remote computer?
If you look at a solution like Sooloos (not to be confused with Sonos), they make an attempt at this. But their solution doesnt allow me my own storage, doesnt let me choose my own interface preferences, and locks me into their architecture. I could live with an all-in-one if it were either exactly what I wanted and/or cost effective, but at $12,000+, it is a complete non-starter in my eyes.
In my opinion, $1,500 to $2,500 for a Sonos or Squeezebox means Im happy with file storage, file access, and user interface. Transport remains the only hurdle Im not satisfied with. Who will step up to the plate and give us an audiophile worthy solution that doesnt break the bank? Im willing to spend the cost of a good DAC plus $500.
Interesting thread.