Oracle issued its first MySQL 5.6 preview in July of 2011. For certain types of queries, there has been a performance gain of as much as 200 percent.
MySQL 5.6 includes sub-query optimizations that improve the query execution speeds. The underlying InnoDB storage engine has also been enhanced for throughput performance.
Under Oracle's guidance the number of new features per release has been cut down to be more manageable. While at the same time, there is more effort going into testing and overall quality.
From a release perspective, Oracle believe that users don't want to upgrade their databases often with big feature releases. It is noted that Oracle has been coming out with a regular stream of maintenance releases though, as the 5.6 release is being developed. The current plan is for major new releases of MySQL every other year. That would place a MySQL 5.6 generally available release for early in 2013.