We've added millions of Firefox users since the move to the faster cadence. Another thing worth noting, we've been shipping updates about every 4 weeks from the beginning of the Firefox product's life. They were noisy and asked you to restart Firefox and prompted with UAC dialogs, and showed a progress meter when you were started. There's nothing new about all of that. We're probably showing that stuff less often now that we're on 6 weeks cycles and not 4 week cycles. We've also turned off the restart prompt for most users and the "What's New" tab for all users.

So, what's different now is that add-ons must move faster to keep up because we're not just shipping security and stability updates frequently, but actual feature updates that can break add-ons. Our big problem is not the noisy updates, but the add-on incompatibility. We're hard at work on that but it's a tough problem.