With regard to what? If you have a developed site and you allow the domain to expire the site will go down. In this instance I would say the implications are huge lol.
some guys sell domains and then specify that it has not been dropped. so what? is there a diff? so what im then asking should be if its re-registered and was prev dropped?
I suppose each case depends on the domain name itself. But if domain name is dropped - most likely that means that current owner is not interested in the domain name.
Some people believe that domains improve over time (aged backlinks, easier to SEO, gains trust etc... so long as its history doesn't contain spam). Once a domain drops into the pool of domains available to hand register as a new domain, some people believe that any trust/backlinks/value/etc the domain has gained over the years, are reset and lost. If it never drops, then it retains its age and perceived value. Cheers James
As said, a dropped domain runs the risk of resetting the PR and age value, as records are deleted for that domain. HOWEVER, the backlinks it has are not necessarily deleted (only if the webmasters of the linking websites delete every single one). This means that if you add new quality content, you can regain the standing it once had. Still, the loss of domain age is a very relevant matter. That's why sellers include that bit of information.