You are correct, adding URL's is the same for either. Here is hte breakdown of what I suggested:
*.domain.com = will allow anything infront of hte domain.com ,i.e. www.domain.com, mail.domain.com, etc.
domain.com = will allow anything if it doesnt have a prefix, i.e. domain.com, domain.com/whatever, etc.
So one just allows for a prefix prior to the domain name. While I cannot find the article, its best practice to perform it the way i have it outlined.
Hope that clears things up and glad its working for you!