Ever tinker with SQL to get the best plan possible but have to track what changed by flipping screens or not sure what session stats change due to the new plan ? Here's the feature for you. It highlights what changed in the tree as well as shows all the session stats that change from one plan to the next. As with all things this is work-in-progress and subject to change.
This is an example on a partitioned table I use to test with of the difference between using a date>sysdate-10 and between sysdate-10 and sysdate. The differences can be see very quickly.