Instead, the next release will be 1.7.0. In revising logging and the web structure, the DHCP-processing core was entirely refactored (the handlers are now much, much easier to understand), more data was made accesible, and extensions now run on a publish/subscribe model, to make it easier for sites to plug in custom code and otherwise do nifty things.
There’s still a bit of work to be done, but it should be ready in a few days. Old config files and custom code will still function properly, albeit with the need to change two lines, which are documented in the README.
I decided against calling it 1.6.3 because, with so much change to the code, it’ll probably need a 1.7.1 release before I’d recommend that production environments trust it, but I’ll be putting it through its paces as much as possible myself, while it’s in development, so it should be stable and mature enough for use in non-mission-critical sites when the tarball gets published.