We have decided to create numerous content laden sites to help promote our main domain. All the sites will be hosted on the same box and IP as the main domain.
Initially the idea was to buy domain-topic1.com, domain-topic2.com etc. These would then be interlinked and also point to the main site.
However, a neater and more elegant solution would seem to be topic1.domain.com, topic2.domain.com etc.
I would assume the first solution would perform better in the engines individually. If they were all listed in Yahoo/ODP then they hopefully would perform well. They would also boost link pop of the main site.
However, using sub domains is easier, cheaper and more graceful.IMO it also looks professional and gives a sense of scale to a site.
But... will they perform as well in engines? Also, if they all have links from the directories, does their individual popularity increase or the main domain's or both?
Does anybody have any experience/comments/theories?