I analyzed the backlinks of my competition and found that these sites get a lot of links from domains that expired and are now just Wordpress blogs with little content and a few links. But these domain have 30-100 backlinks on average (with very little PR usually) that probably help them rank better on Google. I searched for expired domains myself and managed to find some expired ones. How do i know if the domain is worth the lousy $9/yr? 30-50 backlinks? 50-70? 70-100? 100+ ? I'm totally clueless here.. and i found 1 domain with thousands of backlinks, many PR+ too. It's now pending deletion (unlike the previous ones i mentioned which are availalble for registration). How much could such domain be worth from a SEO point of view? I specifically posted this thread in this forum because I'm not interested in traffic/PPC etc.. I'm only interested in the value of such domain to help my site rank better (SEO juice i believe the term is..? I'm a newbie in this industry so forgive my ignorance..)
Personally I think that it would only benefit your site in the short term, unless you build the site right and with the same topic/keywords. It depends what sort of links they are, if they are good quality links, then it may give you a head start.