I involved in a site that gets about 70k web page displays a month. The site is a user based store site where people sell or auction off their goods. There have been requests from a few hundred visitors over the last few months to increase the number of stores on the site. Instead of adding more stores to the one site the thought of creating a network of sites has been discussed.
The thought is that we would create a main network site that would highlight a different site each week and would feature a lot of the stores from a lot of sites on a weekly basis as well. There would also be a page of all stores on all of the different sites. Further, we would have a main chat area on the main site and then each individual site would have their own separate chat as well. Finally, the main network site would have a list of all the auctions inclusive of all networks data and the individual sites would only show their specific auction content. Each individual site would have a link back to the network site.
OK, here is my SEO question. All sites will be either sharing an IP or within the same range of IP address, however they will all have unique names (ex: network1.com, network2.com, etc). Is it better for search engine placement to have 1 site or multiple sites? Will it hurt the current sites placement by adding all these additional networked sites?
thanks in advance.