Thanks for sharing this, @renehoj! Here are the specific talks by Qubes core devs for anyone who might want direct links to them:
Demi Marie Obenour: Reasonably Secure GPU Acceleration
Marek Marczykowski-Górecki: Host and Guest Suspend Under Xen - S3 and S0ix
Marek Marczykowski-Górecki: Linux Stubdomains Status Update