What's new with the reverse dictionary / thesaurus?

The reverse dictionary is getting its first major upgrade in many years. Thank you for helping to test it out!

The overarching goal of the new system is to help you find the right word for your writing needs as fast as possible. Here are the key differences between the new tool (now ready for testing at http://www.onelook.com/thesaurus/) and the old system:

Known bugs / problems and future work