Makes sense seeing as they're focus -- no pun intended -- is pretty much Firefox and its various incarnations throughout desktop and mobile. Expanding their most visible brand to include their entire suite of browser based technologies doesn't sound like a bad idea to me.

I'll take "Focus by Firefox" over "Firefox Live 360" any day. ;)

For tech people, Mozilla makes sense. But your average user's probably only heard of Firefox.

Meanwhile, I'm very disappointed in the expectation of abandonment of the email client I've been using for over 10 years.

It's not abandoned, Mozilla are simply not funding development themselves. Like SeaMonkey, it is community-maintained.