The Dev Team has released redSn0w version 0.9.10b8b which brings only a minor bug fix. According to the Dev Team blog, the "0.9.10b8b update to redsn0w makes the zip files more compatible with the native Windows explorer (which doesn’t like leading slashes in the filenames)." The previous version released a few weeks ago helped users take advantage of the popular SAM unlock method.
In the meantime, the jailbreak community is closer to releasing an untethered jailbreak for iOS 5.1. Currently only A4 and A5 devices on iOS 5.0.1 and lower are jailbreakable. A4 devices can upgrade to iOS 5.1 but they will have to go tethered. Hopefully there is an untethered solution for all iOS devices right around the corner.
You can download redSn0w version 0.9.10b8b from the links below: