My Mac Mini doesn't sleep well.

Brian, I'm thinking it could be so many little things, it might help if you're a little more specific, as in which Mini and OS are you running? Do you have iTunes home sharing turned on? Where does your music reside, on the internal Mini drive or on an external? What exactly is it networked to, a la other Macs? iOS devices? Apple TVs? PCs? and how are they "mounting" the networked music volume?

Just as an aside, I've always really liked Bonjour, and thought it very smooth the way Macs and iTunes inherently advertise themselves over the network. I've also never worried about my Minis sleeping, in fact I've always set them never to sleep because they are so inherently quiet and green. But I do let other Macs in our house sleep and wake, successfully, and Apple's implementation of wake on LAN (wake on demand) works well with them, but then I'm also using an Airport Extreme, so it should.

http://support.apple.com/kb/HT3774

What router or basestation are you using?

Is your Mini involved in anything iCloud related or syncing iTunes purchases to iOS devices?

That's a 2010, with the newer unibody design, so yes, there are fewer reasons to force that to sleep because it is pretty quiet and "green." If that's still the stock 320 gig drive it's 5400rpm. I'm pretty confident you can run that headless Mini with no keyboard or mouse connected, screen share in when needed, have iTunes home sharing turned on, do Time Machine, have a printer on your network AND still expect that Mac to wake and sleep properly, because I do all of those things with several Macs in the house, including a 2011 Mini. So if it is worth it to you time wise you can eventually successfully troubleshoot this. (By the way, did you ever investigate whether it was your Roomie Remote discovery that somehow kept waking your Mini...)

But, that said, I also purposely keep a 2011 Mac Mini running 24/7, because keeping it awake and wired over gigabit makes everything else in the house more reliable in terms of media sharing: there's no trouble with any Apple TV or Mac in the house not finding my iTunes library and when I open the Air Video app on my iPad there's no delay seeing my whole media collection. I do let the various drives and enclosures and external volumes sleep, but the Mini that serves it all up, no. I'd suggest you live with it not sleeping for a while, doing everything you want it to do and see if you come to value that reliability more than the few extra bucks it'll costs over the course of the year.