I'm making exactly this transition right now.
First, spend more time thinking about the interface. With CDs, you just walked over to your shelf and grabbed the disc, probably based on your familiarity with the color of the spine, and the location (alphabetical, by genre, whatever you used). So how are you going to accomplish that with an "all-bits" system? Even a tiny bit of interface friction can make you listen to music less than you otherwise would. And all the expensive gear in the world won't sound better than cheap stuff when it's sitting ther silently.
I really like iTunes on Mac. It's generally easy to use, and I can trust that Apple will keep supporting and improving it. Album art, lots of ways to reorganize, easy lossless-to-lossy conversion for you iPod. A free "Remote" app for that lets your iPhone or iPad control iTunes from across the room, designed by people who take interface seriously (and each version gets better). All in all, iTunes has the mix of features that works for me.
Sooloos/Meridian is another that people love. Big touch screen, lots of enhanced meta-data. But expensive.
All the others -- Olive, Sonos, "rip all your music to a hard drive and use the DAC" -- for me are far less useful from a user interface point of view. How do I browse from across the room? How fast is it to browse a library of 20,000 tracks by hundreds of artists?
Think first about how you want to "touch" your music collection. Then think about expensive DACs (BTW, I use a Halide USB-to-SPDIF bridge to get the bits from an iMac to a Benchmark DAC, or direct USB to Ayre QB-9, both sound great. There is tweaking to do, but don't assume that just because computers use 75 cent parts to output bits, that somehow they can't sound just as good as the SPDIF output on an expensive transport).