Import Skype Contacts.scpt let's you import a list of Skype contacts from a text file.
To export your Skype Contacts to a text file, just select, click and drag them. Replace "\n" to ", "
To import the contacts list from the text file to Skype, download the Import Skype Contacts.scpt script, open it with AppleScript Editor and click Run.
You can customize the message that is sent to your contacts requesting the authorization.
To do this, just change the "Hi, please..." text inside the send command:
send command "SET USER " & contactItem & " BUDDYSTATUS 2 Hi, please consider accepting this request as I'm changing my Skype username to this new one." script name "Import Skype Contacts"
Check Apple's AppleScript Language Guide.