I have been asked in the past how this is different from 301Works. Let me explain: After tr.im shut down, everyone was suddenly worried about link rot caused by URL shorteners, so bit.ly and others founded 301Works, a backup provider for URL shorteners. Everyone was back to not worrying about link rot, but the sorry state of 301Works is, that only 7 URL shorteners actually send in backups of their data, and those 7 aren't exactly big fish like bit.ly or Tinyurl. Furthermore, all data on 301Works is private and will not be usable for research.
URLTeam on the other hand does not rely on the cooperation of URL shorteners. We make backups, if you want it or not. We also publish those backups regularly.
As for the size of this backup: It's 40 GB compressed, uncompressing to about 160 GB of text files.