LimeSurvey is the culmination of several months of work on the 1.85+ builds and marks the end of weekly 1.85+ releases. Therefore you won't find many new fancy features in 1.86 but a very solid version of LimeSurvey. If you run any older version we strongly to recommend to download now!
Btw, if you are using our LimeSurvey service platform LimeService then you don't need to move a finger since we already updated it for you!
PS: We are in development for 1.87 now - if you want to submit new feature request or vote on existing features please visit our fancy idea & feature tracker!