Exactly what happens when you raise your domain level from mixed to native?

I have upgraded all of my NT4 servers, and have a windows server 2003 active directory domain in mixed mode. When I go to native what happens? Do I loose the original domain, and have to refer everything using the active directory domain name?

My old NT4 domain is “campus”, but my new active directory domain is “campus.edu”. When I logon, the domain listed to login to is “campus”. After I go native, will that switch to “campus.edu” ?