I use a lot of hyphen domains and they do fine (no more than 2 hyphens though, and usually just 2) but, I think the largest problem with them is that USERs see them as spam and so may be less likely to click them in the SERPs.

I recently came across a site using double-dashes in between keywords. The single-dash and no dash versions were already taken. Clearly an effort to rank highly (and it did for the primary keyword) with no consideration for type in traffic and additional evidence that dashes alone won't keep a site out of the SERPs.

I also have a client that has a www.keyword1--keword2--keyword3.com domain and it ranks for the keyphrase and draws traffic.

the chance is taking it as spam., i think. i too have bad experience

Using hyphens can help with search engine optimization, because it helps search engines acurately discern the keywords from the domain name. (E.g., A search engine would have a difficult time separating condominiumssantaana.com into the keywords condominiums-santa-ana.com.) To get the benefits of both direct navigation and search engine optimization, I often recommend buying both the hyphen and non-hyphen versions of a domain name, and have both domains point to the same site.

Give me a break, why is www.a1computersoftwarediscountmicrosoft.com
any friendlier than with the hyphen? IMO, in that case the - is friendlier, looks no less weird and just as much of a spam flag! Sorry IMO, people jump on the hyphen with no research whatsoever to backup what they say. I have done research for years and can tell you it doesn't affect anything!

Terry, both are horrible, imo. ;-)

I too had a bad experience ... Any way mnow a days, i avoid the underscores, even a signel one.