Gabriel's reaction to their names can best be described as a mixture of annoyance and relieve. Annoyance, because he and the Winchesters are reluctant allies at best; relief, because it means that they didn't die. Maybe there's hope for Kali or the others.

"Can't say I've ever heard of them," he replies, glancing down to the ring on his finger and wondering if it'd be worth trying to call Castiel over the comms. "Betting they're not that fun, though; Castiel has horrible taste."