Haven't really read either, so take that into account.
I know of the history of the DiVinci code thing through a book called "Holy Blood, Holy Grail," which itself proposes Jesus' decedents are related to royalty in Europe (and more specifically the Monrovians [I'm sure I'm mis-spelling that] in France). Which is interesting, if you get off on the conspiracy thing. The authors of that book (there are three) actually sued Dan Brown from something to do with stealing the story. I think that's kind of lame, the suing bit that is.
Which leads us to the Church of Mary Magdeline, which was built a while ago and really is the only church (despite her gospel that wasn't included in the usual canon) to bare her name. If you look at all of this, you'll find some interesting bits on the Knights Templar and some freemason stuff.
I got into a lot of this on account of liking Robert Anton Wilson a little too much. His new "email to the universe" has some of the things he's written on the conspiracy thing that Brown's book went into.
I bet the reason why the freemasons didn't really get into the Dan Brown fiasco is probably they didn't care. There are enough books that put down the masons for any number of totally unsubstantiated (and some substantiated) things and it's not really worth their effort. But, you know, IANAM (I am not a Mason).