Evasi0n, the jailbreak utility for iOS 7 (including beta 1 and beta 2) is rumored to be patched before the final iOS 7.1 release.
When Apple released iOS 7.1 beta 3 earlier today, many of you were wondering if they had patched evasi0n7. The good news is that Apple has not patched evasion7, according to iH8sn0w — therefore the jailbreak still works on beta 3. Although evasi0n has not been updated to support beta 3, there are some unofficial builds floating around that do support it.
While Apple has not patched the exploits evasi0n7 uses in 7.1 beta 3, it is likely that by the final release (rumored for March), they will indeed fix the vulnerabilities therefore making evasi0n7 incompatible with iOS 7.1
iOS 7.1 beta 3 brought UI tweaks including an updated keyboard, dialer and call screens.