Uptime might not matter for small hosts that do mom and pop websites or so-called "beta" blog-toys, but every time Level3 takes a dump, it's my wallet that feels the pain. It's actually a rather frustrating situation for people who aren't big enough to justify a /19 and an AS#, but require geographically dispersed locations answering on the same IP(s).
I'm not sure why you think you need to be that big to get portable IP space. Policy 2002-3 allows for the issuance of a /22 to any organization which can show a need and the ability to utilize at least 50% of a /22 with multihoming. An ASN can be obtained pretty easily if you intend to multihome. About the only thing that might stand in the way of a small organization is the up front cost, but, even that is less than $2000. Owen -- If it wasn't crypto-signed, it probably didn't come from me.