I've done a little research and found what seems to be the Mac's one true strong suit: they're great for recording.
I've used my current PC for recording, and it's ok, but I've spent the past year finding a suitable DAW without ponying up big bucks to upgrade my PC to run ProTools and then buy ProTools itself (I've made a point not to use PT anyway; I'm not a pro, I'm just a guy who wants to record some damn music; plus PT is turning out to be what's screwing up newer music).
Audacity sucks as a DAW. Yeah it's free, and yeah it's good if you want to record yourself doing a VH impression only on guitar, but again it sucks ass as a DAW. It doesn't recognize MIDI files, it doesn't recognize most .dll effects and plug-ins, you can't use it as a slave program, it crashes on my PC after you have 10 different tracks in the project even though I exceed the RAM requirements ... I could bitch about Audacity all night if I wanted to. I still use it to record one or two raw tracks at a time but I avoid it if I can.
Reaper is basically free and just about the only decent DAW I've found, but it's interface really can make me scream WTF at the top of my lungs sometimes. Effects are buried in folders on top of folders. Using it as a slave for a MIDI sequencer is a bitch. Fading different tracks in and out can get a bit aggravating because Reaper uses a fading tool instead of highlighting and applying an effect. On PC, it's as good as it's going to get, though.
I've tried Mixcraft and it was ok, but my "free" copy somehow became a trial copy and after every project ended, the developers started bitching at me and I couldn't mix the tracks down. Since I didn't have fifty bucks to spend at the time, out it went. I never attempted to use it as a slave to host other recording programs, however, so I don't know how that could've went.
I had Adobe Audition and loved it, but it's essentially everything Audacity wishes it could be. While it is great to use for recording raw single tracks, isn't a good DAW. You can't use it as a slave, for starters.
I've tried Sony Acid Xpress, but I think that's best left to someone wanting to make remixes of another artist's songs. It's limited to ten tracks only anyway, so I didn't keep it around long.
I've had an itch to finally record some ideas for well over a year now. I'm using Beatcraft for drum loops and I'm playing keyboards, guitar, and bass myself. I don't have a band because 3/4 of the dudes who actually play an instrument around here wear tight jeans and want to be like The Devil Wears Prada (buhhhh). That's not what I'm about so I'm just going to do everything myself. I've got the raw material here and ready, just sitting idle, I just have to polish it up and arrange it but I've had nothing but aggravation out of trying to do it on my PC. I can't arrange a single demo (or really polish recorded tracks) because the DAWs for Windows aren't as good as the DAW and recording programs you can get on a Mac. Logic Studio and Logic Pro are great DAWs with a buttload of plug-ins and effects and it doesn't have the sometimes bass-akward interface of Reaper. It seems to be pretty straight-forward. I'll also have Garageband to use until I grab a copy of Logic as well (all Macs have Garageband, which is esstentially a stripped down version of Logic) and I'll probably keep it afterward to serve the role Audacity has on my computer currently.
I'm not buying one because I've bought into the urban legends about Macs and so on. Since I reformatted my PC and installed decent anti-virus software, I haven't had any hiccups. I don't care about gaming; I was never really into PC games anyway. I'm buying a one used as well; screw paying a small fortune for a new one.