I was going to write about how Old Man Luedecke's Proof of Love is a bluegrass album that even people who wouldn't count themselves as fans of the genre would enjoy...and then I found that Herohill had said that already, and a lot more eloquently than I possibly could have. So before I say anything else, I'll suggest you go take a quick look, and meet me back here when you're done.
Back? Good. All that I can add to that is that Luedecke does everything that Ack describes. By playing around with tempo and style, he does an excellent job of showing that "bluegrass" is actually a much larger category than you (or at least I) might have thought. There are songs like the title track, on which he lives up to my preconceived notions...but at the same time, there are also songs like "Big Group Breakfast", which verges on being pop, while elsewhere (like on "Little Bird"), he shows that banjos are good for ballads, too. You've obviously got to have an open mind toward the instrument to really enjoy it, but if you go into it just looking to be entertained, Proof of Love should do the trick.