Possible Duplicate:
Is it better to put hyphens in a domain name?
QUESTION: What would work better for a two word search string as "green shoes"?
Acquiring the domain greenshoes.com OR domain green-shoes.com? Or another?
Any other tips on how to score high with two word searches
Help appreciated!
Sadly, exact-match domains still have an unwarranted ranking weighting applied. Hypenated domains are for those who missed out on the non-hypenated versions, so if you have the opportunity, then get the non-hyphenated one.
Besides the domain (and on-page factors like page titles, content etc), it will be natural back-links that contain that phrase (or related) to your site that works best - hence Adobe Acrobat Reader ranking #1 for 'click here' (since every link has that anchor phrase).
Get them both and set your dns/web server up so they both point to the same website.
But to be honest, SEO goes way beyond just the url name and I would question just how much the URL actually is counted in the algorithm. Things like page titles, headings, links to your site(s), meta tags and quite a few other factors are part of the equation.
