redsn0w jailbreak, 0.8, has just been posted to its official torrents that apparently includes 3GS compatibility (in addition to support for the 3G and original iPhones plus the second-gen iPod touch, as before). Whether it's better than GeoHot's purplera1n jailbreak is unknown, but hey, the more, the merrier -- even the iPhone hacking community isn't immune from brutally competitive market forces, eh?
[Via iPhone Download Blog]
Update: Now it's been announced. Get to it, jailbreakers!