Although the amount of clients connecting with 1.0 may be very little in most cases, it does still happen. We have customers specifically state that they do not want to set up http 1.1 because at the end of the day, some people will not be able to view their (and/or their clients') web sites, which is fair enough.
I hope this doesn't mean they don't deply http 1.1-capable servers, but that they don't actually utilize the virtual hosting functionality based on the Host: header in http 1.1? Not doing 1.1 server-side would be extremely bad for the http 1.1 clients and the general health of the network. By the way, anyone want to take bets about when the next craze about "always on" network service becomes significantly widespread, and how that will affect IP address space consumption? ;-) (No, I'm not an IPv6 advocate, if that's what you're thinking, just putting this all in some larger perspective.) - Håvard