When you mention 2 different libraries is that on the same PC or 1 library each on one different PC ?
Over here - we have the "standard" layout - which is our HTPC that runs the ONLY copy of Media Server (and houses the "official" shared library) to 3 client PCS. These 3 clients have NO local library - and they only act as clients to the Media Server
Then I have my own personal workstation - which has both a connection to the Media Server Library (above) AND it has it's own unique local library (on the PC). It is this local library that I use exclusively on this instance of Media Center. This library is exclusive and not shared.
Another key point to remember is that both libraries (Media Server AND my local one) point to a single media source (Music, Videos and Picture shares - on the home server)
The beauty part of it is that my local PC is the "editor" where I do all my metadata entry etc. It is here that I prep all the rips, add all the tags, test cool playlists and so on. It is also from here where I populate the home server media source folders. So - when I prep, tag and add 5 albums on this local PC - those files then get moved to the server. Over on the HTPC - I have Media Server constantly scanning the server shares for new adds. So a few moments after I complete my stuff over here on my local machine - the new adds appear in the "official" shared library and the clients can access it.
I love the fact that I can do my thing exclusive of all media server activities. There is no syncing changes, no hassles with security and so on.
Plus my local library is the ultimate test grounds for new playlists, views and even new versions of Media Center that can all be tested in a closed environment without wreaking any havoc on the family shared media library.
I would not do it any other way.
Cheers,
VP