The thing often forgotten where D&D is concerned these days is that rules are just
suggestions. There's no Canon Police there, holding a knife to your throat saying you have to use X rules.
I've played D&D long enough now that there doesn't seem to be a lot of new ideas. WotC, in my mind, has hit a point to where they're not putting out much that I really want. What new alternatives they provide just aren't all that inspiring to me. So now I'm looking elsewhere for new and different ideas.
After you play for neary 15 years, it's hard to find something new that you haven't seen or heard of before. Though Arcana Unearthed/Evolved is a bit too rules-intensive for my tastes, I will give it credit in that it provided a lot of neat new options. Magic is certainly a bit different. I'm also fond of the classes from that book. Green Ronin has also been a good company for some new ideas (i.e. True20, Master Class books, etc.). I've found some good stuff here and there as well.
Canon, in your games, is what you make it. If you don't like X rule or X organization, don't use it. If you use an existing setting, feel free to mold it the way you like.
Remember, all those books out there are merely suggestions. The only true rule is that the DM makes the rules.
