Most of the “big guys” will have hundreds of sites per server. Us? Under 50, and even less based on the traffic needs of the accounts.
Speed matters – to you, your visitors, and the search engines. We use high-grade servers for every account. Overcrowding of servers, and mixing the applications on them can be the death of your site. When you become popular, you won’t get blocked for high resource usage. Instead we’ll talk about a solution and implement it!