I like Firefox and don't think it's about to collapse like many users here, but I have already unchecked "Recommend features as you browse" and "Recommend extensions as you browse" along with setting the welcome page for updates to about:blank.

Ideally the user interface for any tool I use should never change unless I actively prompt it to change, and the only notifications I should get would be from my friends and family contacting me or calendars/alarms that I set myself.