I did a quick survey of my hosting options. I'm after something reliable, and fast. To gauge speed I searched alexa.com for each company and recorded their speed ranking. In fact, the "method":http://pages.alexa.com/exec/faqsidos/help/index.html?index=109 Alexa measures the speed turned out to be quite useless to determine true hosting speeds, but they are pretty interesting still. The numbers represent the "load times experienced by Alexa users, and measured by the Alexa Toolbar" which includes time to load the page. The ranking column is the number of sites that are slower.
After I checked the above records I decided to check a couple of other domains out of curiousity.
While it's not worth drawing conclusions on such a small sample it is interesting that these numbers represent the average experience of the user. I _think_ there is a lot of room to improve in this regard. On average Alexa claims it takes two seconds to load a Yahoo site. That's longer than I think it should have to be.
Still, some sites are doing very well even with a two second load time so maybe it's not that important. Keep in mind, if you're trying to portray a slick, cutting edge site, a faster load time will certainly be important. Many people argue that Google don't return better search results over Yahoo, but feels faster, more lightweight because of it's interface, and hence 'better'.