– Between geohot's limera1n, the Dev's own pwnage2, and @pod2g's ipod2g-MC exploits, there isn't a device or firmware that can't be jailbroken. (Yay!)
– They're waiting on @comex to refine his hacks to support untethered jailbreaks (right now, he's only good for up to iOS 4.2 beta 3).
– The Dev's upcoming unlock will work for iPhone 3G(s) owners — and once the iOS 4.2 hysteria dies down, they'll start working on an unlock for iPhone 4's. Basically, unlockers should just sit on their hands for the immediate future.
– As always, proceed at your own risk — and be prepared to lose previous breaks/unlocks. "Honestly unless you love living on the bleeding edge, it's better to just wait for official updates from Cydia/redsn0w/PwnageTool."
– Anyone who wants a payment, or even a "donation" for their jailbreaking tools — run the other way. Fast. "Every legitimate solution you will find for unlocks or jailbreaks will be offered without an extended hand. That's how the iPhone jailbreak/unlock community has succeeded. It's about freedom to do what you want with your $300 device - not about donations, egos, tweets, or 'interviews.'"