The reactions across the board are quite disappointing, to be honest.

All you can do as a customer (or as anything, for that matter) is give up the illusion of control.

This is the Sparrow story: A fantastic product was built, and exchanged for money. The people behind the product were recognized, and were acquired for a significant amount.

Everyone is a winner, and customers move on to the next thing.

What's more worrying is our reaction to an email client going under: it's clearly a sign that we don't have enough well designed products for a system that's been in mass use for more than a decade.