He's a hack whose books I've never been able to get through--cliches and boring characters throughout. I'll beat the rush and say yes, he sells millions and millions love his books (including members of my family). Doesn't change my opinion of his writing in the slightest. It's nice he may occassionally write a paragraph or two in support of conservative ideals, but he strikes me as someone who's careful not to offend anyone so as to affect his bank account.
I havent' read of any of his books for months now, seems to me that his earlier books were better. A couple of my favourites are Cold Fire and Midnight.