I consider email to be essentially ephemeral to begin with, so if Gmail were to suddenly disappear, it wouldn’t really kill me. Also, it seems that webmail is one cloud service that has staying power, as contrasted with the vast litany of failed and gone sites I listed previously. Basically, I consider the convenience of having my email easily accessible everywhere to be more important than the slight possibility of an outage.
Of course, I’m also a paranoid geek. I copy all my email from Gmail and put it into an Mbox file in Eudora, then back that up. So, if Gmail were to die, I’d still be able to bring my email into Thunderbird or the seemingly-mythical Eudora 8 or Pegasus or Mutt or any number of Mbox-based email clients. This seems to be a decent compromise – I don’t trust the cloud, but email isn’t really permanent anyway. It is quite funky to see email from 1998 in my Gmail listing, though. 🙂