GoogleGuy's advice about moving hosts and staying indexed by Google.
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I moved host 5 months ago.
For fear of googlebot missing the move, I was sweating it out.
Googlebot found it within a day.
We try to make it seamless and fast for people moving hosts. Glad it's worked well for folks. My rule of thumb is to bring both sites up on the two different IP addresses and then switch the DNS to the new IP address. After you see Googlebot visit the new IP address, you can probably take down the old site. Doesn't hurt to leave the old site up a bit longer, but you shouldn't need to worry about it.