I started playing with an old mac laptop and a music streamer plus. The convenience was great, the sound OK. I finally "got" what having an i-pod was all about though - you get to hear music that you haven't heard in years because you never think to dig it out. The server in shuffle takes care of that problem. In short, I started out slowly and am now hooked on a server based system.
I'm now on to Mac Mini and just replaced an Ayre QB-9 with a Metric Halo LIO-8 inteface. The DAC's in the MH are, IMHO, superb and you can also use it to record things to the server at 24/192 or whatever sample rate you choose. I use Pure Vinyl to archive records at 24/192 and the Pure Music part of the software for general digital playback. I agree with the recent August 2010 Stereophile article by Fremer - using pure Vinyl with digital RIAA equalization is certainly the best vinyl playback I've had in my house, and my old phono pre (Aesthetix RHEA), while not state of the art was pretty decent. The Music Streamer was a decent budget DAC, the Ayre was great and (with Pure Music) the best digital ever in my house to that point, but the MH is even better. IMHO, it sounds better at any playback sample rate, goes to 192K and has so much more flexibility. Bottom line is I have both better convenience and sound with my server setup. I don't miss a CD player at all. If you haven't yet chosen a computer, I highly recommmend a Mac Mini - it is small, quiet, and has both USB and built in Firewire so you can use pretty much any DAC. Plus, as far as I know, neither Amarra nor Pure Music will run on a PC, and one of them is essential for the best server sound.