Why not combine them? A main server that manages, is aware of changes to, and serves all media; coupled with user accounts and settings that connect to the server.
I started writing this up last night as I was going to start another thread to throw it out there, but haven't quite finished editing. however, since you brought it up, I'll just post it here and answer questions if anyone has any.
Media Server
NOT a Library server (Libraries are managed elsewhere)
Runs in the background on designated machine (faster on machine with media stored?)
Serves all media to all users/profiles
Has no organizational or visual responsibilities (other than naming and location convention)
Cannot be "viewed" or "browsed" directly, only thru an admin user account/profile (see below)
Is aware of all media in all locations
Automatically imports and watches for changes in all locations
Handles codec management for playback, ripping, recording ,etc
Ripping and encoding settings should be system-wide, so should be set here
Handles file conversion required to deliver media to users/profiles (different users/different needs)
Is aware of all devices and connections, and their drive/media sharing allowances
Manages any cache files (same copy is shared to anyone requesting a less then full-size version?)
Ideally would manage access rights for users/profiles (admin, user, party)
Profile or User This is a users individual, customizable interface to the systems Media Server - these things can optionally be shared with other users/profiles
View Schemes
Playlists & Smartlists
Ratings
Tags and their settings (defaults to Media Server settings, but can be adjusted)
Playback settings (gapless, level adjusted, etc, default to Media Server settings, but changable)
Playback stats
Visualization settings
Handheld settings should probably go here, as they typically belong to a user, so are an extension of them and their playlists and preferences
Custom library fields should be setup here
Podcasts are setup and managed here, but are stored on the Media Server and available to other users
TV can be viewed live*** or recorded, programs can be set up to record and deleted from here (deletions might need other users to allow deletions, to avoid fights)
*** This is true no matter where the actual tuner is installed, as long as that device is connected to the Media Server
Devices This is any device that physically (or wirelessly) connects to the Media Server (including playback only zones)
Other computers
Handheld devices
DLNA devices
Web connections
These may or may not have Media Center installed on them.
If MC is not installed, the settings are automatically set/determined by the Media Server
If MC is installed, settings can be adjusted from what the server defaults are
Resolution, network connection speed, sound and video card capabilities, output connections are set per device
Devices settings will be used for any user/profile connecting on them
Most/all will allow playback on them
Putting it all together Pretty much all the settings are stored by the Media Server, and are given/loaded to the device based on the Profile that connects
The Media Server and the Profiles are separate entities the Media Server is the heart of the system and manages everything
The Media Server does most of the processing and just sends the smallest possible file (if conversion is requested or necessary) to the device, based on user/profile settings, and/or limited capabilities of the connection (wireless for example) or of the device (small screen size on mobile device does not need 8mb image files sent to it, for example)
Maybe this helps...
Think of the Media Server as the books and magazines and videos in your local library, all sitting on their shelves.
Think of the users/profiles as the card catalog, they know and document and help you find the books and magazines and videos on the shelves
Think of the devices as the thing you use to manipulate the card catalog to help you find the books and magazines and videos on the shelves (the actual card files, or computer, or tags on the shelves)
The Librarian is the connection between the card catalog and the books and magazines. it knows how to take your need/request and fetch the best possible version of the book, magazine, etc, as relayed by the card catalog.
MC should hide the Librarian, and just know the best way to get what you request, based on all the information stored in the Media Server about available media, connections, and playback preferences and abilities, and just makes the right connections internally to present the best version to the user/profile.
I think this solves most/all of the client server requests and debates I've seen over the years. Other than the (possible) difficulty of implementation, I don't see any downsides to this approach.
I started a thread on it a while back, it has more details, but Jim said it was confusing
i hope this helps
http://yabb.jriver.com/interact/index.php?topic=57440.0