Originally Posted by Antonio

nah, not true, moved hosts many times, often it would take me 3-4 days to move all the sites (so, they are completely down for 3-4 days) and then I see no change in Google traffic at all;

same goes for ip changes - as long as your site is old enough, I don't see how that matters at all and the only exception I can think of is if your site is moved to some malware / shitware infested server