Ooooo, will this end up in Konsole / konsolepart? Or will it be a new app?

It'll be a new app, but it does provide a drop-in replacement for konsolepart (along with also having a QML module API for embeds into Qt Quick-based app, closing a gap Konsole currently leaves open). I'm sure it'll be some time before it would be ready to replace Konsole as default, also because conversations like that take some time and are a community process.