Just got early access. As a consultant and lecturer, I live in Keynote and I've had very high hopes for this product. It might be too early to tell but so far I can't say that it's a major productivity boost. Nice UX and some nice templates but not life-changing so far. TBC
I've been a fan of Calendly for years but it has its downsides. Available for Gmail doesn't let others access your calendars but helps you to easily paste suggested times in emails. Simple but handy when you mostly deal with people outside of your organization.