I just closed the Plasma 5.4 kickoff meeting. It was well attended with lots of Plasma devs and VDG members there. Here’s the minutes.
If you’re looking for a way to join the team of beautiful desktop developers (you can read that both ways and be correct) there’s plenty to do now. For example the VDG have written a nice design document on System Settings which they need someone to help implement.
Plasma 5.4 is scheduled for August, it’ll be a great addition to Kubuntu 15.10.