WEBZINE

The information at webhosting.info is a valuable resource. It is interesting to see the trends of web hosting companies. A list of the top 50 web hosting companies worldwide can be found here
The list data is not an entirely accuarte guide as to web hosting clientbases, as it includes a number of large companies which focus primarily on domain registration/URL forwarding as opposed to web hosting, and it also includes a number of very large private domain speculators.