Unmap an old domain in order to map a new domain

Hi,

I'm using the domain mapping plugin right now and I'm doing it for a subsite that is configured for sub domain. (example.mysite.com) I mapped a TLD for this sub domain and everything has been going fine. However, I now want to change the TLD to a .org. I was thinking if i was to just unmap that old TLD and map the new TLD to my sub domain.
However, I now have some concerns.

Will this cause any database issues or any thing like that? We haven't published the site yet, so I'm not worried about link issues, but I just want to know if it is as easy as I'd like it to be... Just go in and unmap the old domain and map it with the new domain? Or is it more complex than that?