Just some comments on the script you purpose:
-You should probably check the date from the Last-Modified
HTTP response header, that way you won
't be dependant on the guys from www.mirc.co.uk
always putting the date in a comment on the 3rd line. Also, you should check the date as soon as possible so if the file on the server isn't newer, you can disconnect immediately, whitout wasting bandwidth. Or even better, use the If-Modified-Since
-the best way for updating the servers would probably be to loop through the downloaded file, interpret each line and server -a
it. This wouldn't replace any additions the user made to his/her server list, only update/add servers.