Many dependencies have been removed, including a reliance on TemplateHaskell along with simpler documentation, bug fixes and some new configuration options.
The initial motivation to put some effort into making this release was the contribution of @minad with his pull request this January which showed a number the problems with the implementation. Following a discussion, @minad decided to create a fork, tasty-auto, to avoid introducing breaking changes and save time.
I finally made some free time this week and committed to making the new release based on those changes. After some review, suggestions and agreements on tasty-auto/#1, @minad gracefully decided to deprecate tasty-auto in favour of tasty-discover in order to consolidate our efforts into a single library.