Hyphens IMHO do not infringe upon SERP as a matter of fact search engine algorithms dont even see the - so some of the a-b-o-v-e examples will rank just as high as the actual word.
Cera I have to agree with your above statement but i must add that when most people using a search engine are typing in their query they usually type the (space) between words, They do not search for domainnameregistrationwebsites so for someone trying to key in on keyword enriched domains I would reccommend using the - but if you are strictly a domain speculator then these are hard sells because there are many variations to every domain available for reg fee.
I personally have started a test regarding the above mentioned w-o-r-d type of domains, This domain in reference was purchased and set live on Sept 18 it has been visited by search bots and has some pages indexed, The stats for this are comparable to other sites with the same content, The search engines recognize it as the word itself.
On another note, I have read in here that the advertising media's such as TV radio, newsprint ect have all been mentioned in this thread, I for one would like to know who if any of you are currently advertising your domain in a TV campaign? I think that the majority of posters in this thread rely heavily on search engine traffic for their websites, and there is nothing wrong with that but unless your have 13k for 12 /30 second TV spots on a weekly basis I would advise you to BUY the domain you feel you can work best with, If you are relying on search engines for your traffic and the best avaialable domain that describes your site and is the keywords that you want most has -'s then go for it...Buy that one and promote it. Just because domain speculators SAY -'s domains are a hard sell does not mean that they are not suitable for what you want to do with it.
Remember you are getting most of your traffic from SE's unless your advertising budget exceeds 500k annually, and if you have 500k annually to market your domain then talk to the speculators about buying that single word domain you can afford it.
Just my 2cents,