Once thats done the domain will be in your hosting control panel and you can do what you like
If you want the contact details etc changed then expect to get in touch with nominet and pay £££ but really it isn't necessary if you have it in your hosting account, especially if it is your friends domain name
Oh yeah, I said the tag renaming cost me a fiver - my mum transfered her freenetname domain name to my hosting when she changed from her dial up to broadband - she no longer dialed with freenetname and now went with ntl, so had to transfer her domain - catch is the domain was free, so they wanted £25 to let the domain go