Actually, the "love interest" aspect was my least favorite part of the book. I'm reading his first book in this series right now, and it's also fairly annoying with the love interest.
For the record, though, it's just as well-researched a thriller as The Da Vinci Code, sending me to the computer multiple times to look up junk.
And the ending was kind of flat in TDVC. I got the feeling he had this really great idea for a book in that vein, and then didn't know how to end it. Sort of like an SNL sketch.