I think the search engines have got a bit smarter to the subdomains being the keyword.
And regardless of using subdomains or folders, make sure the content fits the keyword.
I tend to go towards a keyword rich domain name.
If using a company domain, think about it a bit.
If people know you by another version, then register the other version.
EG: Coca-cola company has coke.com, etc
Now this part, there is some debate off and on if it is truly worth it for
seo purposes. But what the hey, do it anyway.
And that is having in your meta tags, the keyword: xxxxxx.com (your domain name).