First, let me get out of the way that Andy Diggle's scripts on "Thunderbolts" are good. I enjoy them, they're a nice take on the "Thunderbolts" concept of a villainous team and their connection to the government. He'd already done an excellent job on a book about less-than-reputable characters ("The Losers") and Diggle's sensibilities seem in line with the general idea.
That said, as someone who's growing increasingly tired of Marvel's "Dark Reign" event, I wish that he'd ended up in charge at any other time than now. Don't get me wrong, Diggle's done a good job with the "Dark Reign" era of "Thunderbolts." But with "Dark Avengers" also featuring villains-as-heroes, and Norman Osborn appearing in 37 titles a month (sadly, only a slight exaggeration), "Thunderbolts" has been playing second fiddle to the entire Marvel Universe in terms of a selling point.
Fortunately, what Diggle's scripts do bring is a strong sense of drama and action/adventure. Songbird and Black Widow's escape attempt from the Thunderbolts is perfectly paced, and I appreciated that it's never easy to look at the set-up and know just what's going to happen, even though it all follows through in a logical matter upon reflection. Pop Mahn and Carlos Rodriguez help in that regard; Mahn's pencils remind me of a cross of Jae Lee and Alex Maleev these days, and they pull off both action scenes and the quieter moments of the comic quite well.
There's a lot of fun stuff going on here: the rifts in the team, the surprise new leader, the identity of Scourge. But by being tied into "Dark Reign," it's hard to feel like this is going to last for too much longer. Still, Diggle's done a good job with being handed a strange situation, and I'll be sorry to see him leave. Hopefully Jeff Parker will be able to pick up the pieces left behind and run with them; there's a lot of potential in these characters, and hopefully they won't get entirely thrown out with "Dark Reign" and its inevitable conclusion.