That case was about forcing a provider to release the information, but in Google's case, the gmail subscriber has already given authorization for them to release information.
Earlier thread on Delaware Blogging case:
http://www.freerepublic.com/focus/f-news/1462665/posts
Decision threads:
http://www.freerepublic.com/focus/f-news/1497829/posts
http://www.freerepublic.com/focus/f-news/1497858/posts
Another article on it:
http://www.delawareonline.com/apps/pbcs.dll/article?AID=/20051006/NEWS/510060363/1006
Thanks for the ping.