I think [spoiler]Angelique is unsure whether or nor Quentin killed her (ha, I can't believe I just wrote that sentence--only on DS). At his point, however, she wants to frame him and eventually save him by implicating Maggie. Even Quentin comes to believe that Maggie is just like his former wife, Angelique, and that "Alexis" is a sweet, caring woman, totally different from her sister. So I think Angelique smirks because she knows she's going to take care of Bruno very soon as part of her plans. Angelique, of course, can't really control all these variables even though she thinks she can.[/spoiler]