Currently, in the /sites method, a site can have a site_state of: normal, open_beta, closed_beta, or linked_meta. This makes it easy to tell if a main site is in beta or not. But it becomes a 2 or 3 ...
In 2.0 there are the site_type and site_state fields. On Meta sites these fields give the same information, site_type = meta_site and site_state = linked_meta Instead it would be more useful if ...