I can't figure out how your comment that "understanding mistakes will happen" is compatible with 99.999% uptime.
I'm of the opinion that 99.999% for an individual instance isn't particularly achievable in a commodity hosting environment. That kind of uptime doesn't leave much room for the mistakes that you and I both anticipate.
I do think that 99.999% is doable for a properly distributed whole-system across multiple geographically-dispersed datacenters.
I think Joyent has gone wrong in promoting individual instance reliability.
