No single technique works best for every site so weigh the pros and cons for your site before you make your choice.

I have registered before a lot of domain names without hyphen. Domains with hyphen are considered lower quality among domainers community but for business it is perfect.

I recently registered some domains with hyphen: When there are no available .com for 2 very good keywords it is better to get the domain with hyphen then .org .net etc.

Also, some 2-3 words domains as previous post mentioned are not easily to parse. I have written some domain name parsers and for most 2-3 words domains there are at least 10 possible ways to split on word parts. The task to disambiguate is not easy for machine (Google do it best). It is more easy for human do disambiguate, but there are a lot of cases that it is difficult, especially when words are longer.

So, domain names with hyphens (when 2 words are longer), is better for business IMO.

Engines do give value based on wether there are hyphens in the domain-name or not. That's a fact (and okay). But there are certainly limits involved. So I would say if you have one or two dashes it is okay (having 1 certainly is if you are connecting two keywords). Having more than that indeed looks spammy and is not a good practice. Not in the eyes of the engines and not in the eyes of the people seeing the serps.

Just to share a story, I used to own the domain name Webmaster-Resources.com .

WINDOWS Magazine, which had 1 million subscribers at the time did a full-page write-up. They left out the hyphen.

Ouch! We changed to SitePoint not long afterwards...

Regarding SEO - I think search engines must realize that the most appropriate domain names for a particular site have probably already been taken.

Therefore to rank a site based on domain name would not be very fair.

Yes, as website builders we must understand what search engines are looking for and optimize our sites, but also search engines must continuously tweak their algorithms as internet trends change.

Therefore, I would hope that the clever people at google realize this and increasingly reduce the weighting of domain names. If you build an honest site, with good content it is the job of search engines to appreciate this. Just like a dictionary changes as peoples use of a language changes.

Conclusion - Just choose a domain name that you imagine people could easily remember and would be easy to tell somebody over the phone - with or without hyphens!

It doesn't really matter.

http://000fff.org/whats-in-a-name-tips-for-naming-your-startup/

Going with the hyphen is OK if you own the domain without the hyphen. You want to capture emails and traffic from people who type in the domain without the hyphen. You can almost always get a hyphen added to your domain name, but the reverse is rarely true. For example, on-startups.com is available, and has little risk of being registered.

I'd personally go without hyphen. Search engines are now capable of splitting single-word domains into multiple words. Also, for projects where I want to combine words for my domain name, I tend to use WhoisMatrix.

I'm going to go completely against the grain and argue in favor of the hyphen.

Because:

1. In the world of social media and search, people don't type in your domain name. So it doesn't matter.
2. Search engines really really really like to see keywords in domain names. It's probably more valuable to rank higher in search results than to eliminate a hyphen.
3. It's really not that bad to say on the phone. Compared to what, spelling "Xobni?" But they're doing fine (for example).
4. If people remember your company name they'll find it on Google. So it's better to have a memorable name than eliminate hypens.

I think your primary domain should be an unhyphenated domain name, and be as short as possible.

While I disagree with @waxingibbous about if you owned goodidea.com, Google is smart enough to see that as two words without the hyphen. Having said that, I do believe you should purchase secondary domains (that can contain hyphens) for SEO purposes. I have purchased several domains with hyphens that point to my primary domain, and it APPEARS to have improved my SEO as a result.

I must argue one point of using a domain with a hyphen.

When people type your company name into a search engine, lets say "Experts Exchange" (to use an example from above), they will almost never search for it as expertsexchange unless they have heard of you previously.

However, if someone searches via the keywords "experts exchange", or they separate parts of your company name when they are not supposed to, ex. barndoor vs barn door, it is my understanding that you will receive more hits because people will search for you with separate words rather than just one and this is how Google will read your page.

But, try it out for yourself :)
As with everything else, it's situational.

I would avoid a hyphenated domain for these reasons:

1. It conveys inferiority (especially to the site w/o the hyphen in their domain) in that you accepted a hand me down domain. In addition it confuses users as to if your site is affiliated with the hyphen-less site.

2. It looks junky and spammy. When I see sites like las-vegas-info-site.com or dot-net-developer-tips.com I think spam site. As a matter of fact the more hyphens in the domain the more it subconsciously conveys "spam" and "avoid site" to the human brain (mine anyways, by an exponential factor).

3. Many SEO experts (I'm not one) will tell you that hyphens in the domain with devaluate your search ranking.

All that being said I would find an original catchy domain name, then try to register the hyphenated version to avoid competitors/squatters from doing so.

Without. You don't want to be saying, "Check us out at 'market-hyphen-sense-dot-com'." It sounds silly and unoriginal.

The longer and more complicated the domain name, the less likely your customers or the media will be able to type it correctly. This may not matter but probably does.

I think you ought to look for a domain name without a hyphen in it. Hyphens are unusual in domain names. People trying to find your site will often type the unhyphenated version by accident.