hmmm singular for a business? It would depend on the product or products the business offers. for example........
ev1servers.net . They offer a wide variety of servers(linux,windows,pentium, celeron) and so on . servers fits it perfect.
IBM(international business machines) this is saying they offer a wide variety of product.
Namepros.com Would you rather this be namepro.com implying that there is only one person that knows anything about names on this site?LOL