Harry Dresden is a likable character, he actually reminds me a bit of Horatio Hornblower, one of those solitary, introspective, self deprecating, ladies' man. 
 The book is cleverly written (I dig the Branson references, I live near there), the idea of a wizard for hire is certainly an interesting one. The modern setting works well, though I'm not fond of contemporary magic, and while the limits of Harry's abilities are undefined in this book, there are definite lines being established for how magic can be produced and used. Also the incompatibility of magic and technology is a fun plot tool. Lots of potential there. I'm envisioning special "Hazekiller" type characters trained with primitive weapons to offset the advantage wizards have against tech. 
 A little language and innuendo. 
 I'll be interested to see where the series goes. I don't know how long I'll stick with it.