Yes, DevTeam released new version of their software. First of all, please, do NOT use unofficial software from unknows sites (f.e. quickpwm.com). We recommend to download from torrent or official mirors.
We regulary publish latets software and firmware links. Use them or the same ones from DevTeam site.
iPhone 3G + NO UNLOCK: If you do not need unlock, you are using your iPhone with one carrier or you hae factory unlcoked iPhone, just restore or upgrade to 2.2.1 using iTunes and use QuickPwn to jailbreak and add Cydia and Installer.
iPhone 3G + UNLOCK: you need to preserve current baseband software. Preserving the baseband will ensure that you can still use “yellowsn0w” the iPhone 3G unlock application. To upgrade your phone to 2.2.1 and preserve the state of the baseband you need to create a custom .ipsw with PwnageTool. This custom .ipsw will not contain the baseband update but of course will still allow all the cool new stuff from 2.2.1. PwnageTool is only available for Mac OS X.
DevTeam updated yellowsn0w to version 0.9.7 to work with modified (!!!) firmware 2.2.1, in which you preserve old baseband from firmware 2.2.