Yes, this is an important lesson about redesigns. I saw a couple people brush off the Snapchat redesign angst with, "Meh, people will get over it", usually with links to the (admittedly accurate) Oatmeal comic about Facebook layout changes [0]. And while that's certainly the case sometimes, don't count on it as a general rule: Digg demonstrated conclusively that a poorly-received redesign can torpedo the entire company. Proceed with caution.

[0]: http://theoatmeal.com/pl/state_web_winter/facebook_layout