Prototype 1.5.1 Out! Scriptaculous 1.7.0 *Not* Compatible. :(
Congratulations to the Prototype team for rolling out Prototype v1.5.1! :D
Sadly, the current stable version of Scriptaculous (v.1.7.0) is not compatible. In Safari, calling any Effect will fill the Javascript console with an infinite number of “Maximum call stack size exceeded.” warnings.
You’ll need to run the Scriptaculous v1.7.1 beta 2 to avoid this issue until a new stable version comes out.