The Ruby project has done a new major release on Christmas for their popular programming language. Ruby offers performance speed-ups but without severe incompatibilities, according to the release announcement.
Language changes to Ruby 2.1 include the default values of keyword arguments can now be omitted, suffixes for integer and float literals, and def-expr now returns the symbol of its name.
To Ruby 2.1's core are new methods, the RGenGC generational garbage collector, new environment variables, bignum performance improvements, standard library updates, and plenty of other changes.
More details on Ruby 2.1 can be discovered from the Ruby-Lang.org announcement
and its NEWS Git file