I see 'compatibility' as a very minor issue at this point. If you choose the right hardware, and spend just a modest amount of time following a good guide to set everything up, then everything works.
Once you've set up a system a time or two (I've created 6 Hackintoshes from scratch now, and installed on 2 laptops, and 3 pre-built (AMD) desktops) what you need to do becomes fairly routine. On my most recent build, using a Gigabyte GA-G31M-S2L, it took me 20 minutes from build, to fully working 10.5.3 install that screams. Everything works, all system components, add on cards -that can't even even be used with a real Mac other than the MacPro- sleep/shutdown/restart every application that'll run on any Mac- all work. I didn't even open the terminal ONCE! I didn't myself touch a single kext file.
This week, I'm doing a new Windows based PC build, and I purposefully picked an ECS board that I have no idea right off if it's Hackintosh-compatible or not, just to see if I can also get a dual boot OSX install on it without having a clue if it's been done before on that board or not. A board I know is supported no longer presents even the slightest challenge, and that's no exaggeration. About the only issue that's cropped up for me recently to spend more than 5 minutes figuring out, has been the '45nm bug' using Wolfdale and Yorkfield processors with OSX. Even that took maybe 10 minutes of reading other people's guides to straighten out. The same will be the case for anyone that just gets used to the set of rules a 'Hackintosh' has.
To put things in perspective, with my last build, installing Windows XP 64-bit was BY FAR, vastly more of a challenge than OSX on the same hardware! And that's not to say installing XP x64 was all that hard, just OSX was that easy. Finding all the x64 drivers was much more of a PITA than anything on the OSX side! (Especially Microsoft HD audio). On the OSX side, everything just worked OOB. Even the graphic card merely required a small change in the apple.Boot.plist to enable full QE/CI, and that's it. (At this point, even NVinject and other tools like that are largely unnecessary so long as you use supported cards).
With Hackintosh builds, you simply have to change your thinking slightly about what is the 'norm' as far as platform rules. The machines are perfectly stable so long as you play by the rules. If you login as root and go screwing about with the terminal like a nutcase, you can easily screw up a real Mac or a Linux system. Likewise, go installing core system updates straight from Apple willy-nilly on a Hackintosh and you'll screw it up. But learn and follow the new set of rules, and you'll have a stable, 100% perfectly working machine.