There's a meme floating around the blogosphere to the effect that these church burnings may have been part of a Methodist vs. Baptist proto-masonic conspiracy. This meme isn't getting any traction at ground zero because we know how stupid this meme is. There's no serious sectarian strife between Methodists and Baptists here. Period. It makes more sense to speculate (as some have) that the burners did pass by more affluent churches, but that's probably more to do with socioeconomic class conciousness than anything.
Another thing: some bloggers have made much of one burner's profession of Satanism, and the kind of anti-social rhetoric these guys posted to each other over the net. I think that's relevant, but not the way some folks want it to be. The notion that these twits were in the grip of some Dark Satanic Power is obviously tempting, but let's get real- "Satanists" are poseurs. Anton Levay made no bones about it-the Satanism thing was just a hook for his highly theatrical athiestic evangelism. These kids' Satanism schtick was more a symptom than a cause; it's Bad Boy Big Talk. It's part of the rhetoric these clowns used to turn their pathetic activities into a Wagnerian Happening. But churches and other houses of worship, respectable businesses and PTA meetings are full of guys who, as youngsters, drank, cursed, professed shocking religious/political/social values and reveled in Bad Boy Big Talk (and many of their well-behaved upstanding wives are yesterday's polyamorous bisexuals.) Their surface-level shockingness doesn't reveal the core wickedness; it actually concealed it. It made them fit in with many, many other college kids who act "bad" but would never do something so evil.