Today saurik released in Cydia a new version of the mobilesubstrate plugin making it compatible with iOS 5 beta 1. Mobilesubstrate is the basis of many tweaks that immediately after the release of iOS 5 beta 1 became incompatible with the new version of the operating system operation. This update should solve any problems you had with SBSettings, FolderEnhancer or other such tweaks that run on top of MobileSubstrate. I haven't installed any of the tweaks to see if they work without problems, but if you have iOS 5 installed and jailbroken then you can try them too.
The new version of MobileSubstrate is available in saurik's repo which we all have already added to Cydia.
