Drupal Domain Access SEO Issues

[talltrees]

I'm working with a new developer to redesign several Drupal sites and have 3-4 sites with similar designs and modules. The developer is keen on using Drupal Domain Access to make maintenance and sharing user information easier. Each site currently has a unique domain and content (although the sites are in related niches).

Are there issues from an SEO perspective with the Drupal Domain Access Module? With only one instance of Drupal on the backend will Google somehow not view these as independent sites?

Thanks for any info!