Compared to our last release, we’ve given you the ability to quickly change your boot or recovery logos and enable “verbose” booting.
After reading the brief Q&A on our wikee, feel free to ask any questions below in the comments. Briefly though, if you’re already happy with your current jailbroken system (whether it’s via PwnageTool or blackra1n), and if you don’t want boot logos, then you can safely ignore this post and we’ll continue the wait for Apple’s next release together 
Otherwise go ahead and try some new boot logos using redsn0w, or use it for fresh jailbreaks. If you use it on an already jailbroken phone, be sure to checkmark “Already pwned” and don’t reinstall Cydia again (doing so will probably make Cydia lose track of what it has installed).
Caution: if you’re using the ultrasn0w or yellowsn0w unlocks then don’t be tempted to update to official 3.1.2 just to use redsn0w (and remember, redsn0w still works at 3.0 anyway). If you update to official 3.1.2, redsn0w will still work but you’ll lose ultrasn0w and yellowsn0w. There is geohot’s blacksn0w for those who updated to official 3.1.2 but there are still wifi problems with the unlock at that firmware in a small number of cases. iPhone 2G unlockers don’t need to worry about any of this, since BootNeuter handles all that regardless of firmware version (BootNeuter is installed for you by redsn0w if you have an iPhone 2G and choose “unlock”).
This version of redsn0w does not provide an untethered jailbreak for those of you with brand new iPhone 3GS, iPod touch 2G, or any iPod touch 3G. redsn0w will jailbreak those but it will still be a tethered jailbreak until some new exploit is found and released.
As always, redsn0w does not update your firmware version. You use it with whatever firmware is already running on your device (and you point redsn0w to the IPSW corresponding to that firmware already running on your device).
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