Saurik declares iOS 8 – iOS 8.1 jailbreak is ‘stable enough'; enables the ability to
 

The Pangu jailbreak for iOS 8 – iOS 8.1 may not be ready for prime time when it was released couple of the weeks back, but one must give credit to the Pangu Team and saurik for releasing a series of updates to fix most of the issues.

saurik had disabled the ability to purchase jailbreak apps and tweaks because he believed that iOS 8 – iOS 8.1 jailbreak was not stable enough. However, with the release of Pangu 1.2.1, Pangu Untether 0.4 package, and Cydia 1.1.16 update, he has declared that the jailbreak is “stable enough”.

http://www.iphonehacks.com/2014/11/i...le-enough.html

if you want to jailbreak your iOS device, do it now.
Backup with iTunes
restore your device to 8.1
Jailbreak with Pangu 1.2.1
restore data from iTunes backup

Apple is poised to release iOS 8.1.1 which also fixes one of the exploits used in Pangu jailbreak. Once they release 8.1.1 the signing window of 8.1 will close, meaning that if you miss that deadline, you cannot upgrade your device or restore it to 8.1... and thus have no JB.

8.1.1 promised speed boost for old iPad and 4S, as well as fix Wifi issues. Most of the WiFi issues can be resolved by doing a network setting reset in the settings of your iOS device though...