Few questions about Portals

[computerhighway]

I am looking to start setting up Portals. When I click to create a new portal, the URL option is not editable and just says None? What is the purpose of the Is Default? Will the main site itself be now considered a portal?
As there is no documentation for the Portals use at the moment, will appreciate if you can write briefly how the portals are supposed to be setup and used.
Many thanks.

[yuri]

Documentation will be written soon.

Default means that url will be shorter w/o id: http://domian/portal
If not default: http://domian/portal?id={portalId}

You can use mod rewrite on your server to provide an ability to access by another url, e.g. subdomain http://portal.domain.com