I try to strike a balance between having some domain that people can remember and including the keywords.  If my dream domain is not avalible (it never is), I get creative and play around with the domain.  It’s funny because the little words you add can actually help in unexpected ways.  (For example - buycars.com clearly won’t be avalible, but buysomecars.com might be.）Really long domains are a pain, but if it is actually a phrase people can remember, it might work out.

When I can’t make up my mind like that, I usually grab ‘em all. Why not? Experiment.

Some people go for using dashes in their domain name.

A lot of people say “No dashes. Unless you never want people to type in the domains.” However, I’ve personally ranked both domains with dashes and domains with foreign TLDs for their exact phrases on MSN, with little or no SEO efforts.  Not as much luck in Google, but the one domain with a dash & a .org extension ranks #1 for it’s term in MSN, and the site isn’t even built out. It also doesn’t have any backlinks - it was just a domain for a PPC campaign with a temporary page on it.

With hyphens (-) or underscores (_), as well as keywords in the domain name, its becoming more difficult to be sure of the benefits (if there are any at all). If you have a look around on the net you’ll find all sorts of views on these issues, with the majority of these reaching the conclusions that having your keywords in your domain no longer does anything. There is a similar argument to the use of hyphens or underscores, with sites appearing to be penalized for having more than one of these in their domain (thought to be due to Google considering these spammy).

I would agree that it is more important to pick a domain that is memorable, something short and witty, as you are more likely to increase your repeat visitor rates as apposed to a chain of keywords joined together with hyphens. I personally wouldn’t remember a site with a domain like that, would you?