There are reasons for that.
Robert Wolfe - one of the exec producers - posts regularly on Jim's message board and has talked about a LOT of this stuff. He'll even answer direct questions.
The reason they haven't shown "Storm Front" yet (which is NOT a direct adaptation of the book) - is b/c they had to reshoot it after they made changes in casting and stories, etc. It's currently slotted to be episode 8.
Even the original pilot - (the 67 minute version, not the 2 hr one) - isn't a direct adaptation of "SF" (yep, I have sources, I've seen the 67 min version - I don't think anyone's seen the 2hr one) - there were a LOT of changes made just for the original pilot ep. And the opening titles were way cheesier.
This episode wasn't meant to be a retelling of "Fool Moon"; the series itself is NOT supposed to be a retelling of the books. It's 'based on' the books, it's not a replica, but it keeps the flavor.
The best way I can describe how it's working is to use "The Prestige".
If you've read the book, you know that it is VASTLY different from the movie that was released in October 2006. However, the movie kept the 'flavor' and 'themes' of the book when it went to the big screen. There's no way the movie could've recreated the book in a visual format - the thing's long enough as it is. There are changes that have to be made when moving from one medium to the other.
The same happened w/ Dresden. They've taken the mythology of the books and reshaped it for the TV series - mostly so it works w/in their budget constraints and w/in the limitations of visual media.
As long as the flavor and themes keep going, I'm all good w/ what they've done. Except that stupid drumstick.