For those of you who may care (and understand what I'm talking about), here is what the problem was. A month ago, when I changed over to f5hosting.com, register.com somehow botched the propagation. There were a few people who still got the old-old site, maybe 10%. After a month, I finally got them to repropagate my DNS settings.
Everything should have been fine, except that about 24 hours later, my hosting company changed the IP address of their DNS servers, in the middle of the propagation window. My best guess is those of you who couldn't find the site this past week were on ISP's who got propagated first with the old IP address. 75% of people who could find the site, were on ISP's who got propagated with the new IP numbers after my host changed servers.
Anyway, we'll see if improvisation.ws clears up. If it does, I may just stick with improvisation.ws and keep improvresourcecenter.com pointed here as well.