Robert_Charlton - 8:07 pm on Sep 25, 2013 (gmt 0)
Hosting is often not a primary speed factor. Things like image size and the number of http calls affect loading time a lot more.
IMO, speed is a negative factor when you have a painfully slow site... definitely when it's slow enough to cause visitors to bail and return to serps. On Pandalized sites, I often see it as a problem along with other factors, but I've never isolated it out to see if fixing loading time alone would help. I just fix it.
I don't think that shaving milliseconds off of a fast loading site, though, will directly improve rankings... it's not that kind of a race... albeit I believe that the improved user experience in the long run can help you.