Google says that it didn't change anything on its side so this appears to be solely Facebook's move, and it looks like the final blow. The Gmail contact import button is also gone from Friendfeed, a Facebook property since last year.
This war all started earlier this month when Google banned Facebook from accessing Gmail contact data by tweaking its Terms of Service for its Google Contacts Data API so that websites which access Google Contacts will need to offer access to their data too. Facebook has never allowed users to export their contact information.
The social networking giant still wanted its new users to find out whether their Gmail contacts also have Facebook accounts, so it implemented a workaround: the website told its users to use a Google feature that helped them download their own data, and then instructed them to upload the file back to Facebook. In attempt to convince you not to take your contacts to the social network, Google then fought back by showing a big warning message when Facebook users came to export their contact data from Gmail.
It appears that Facebook thought this would hurt its image, so not only has it removed the instructions and direct link downloads to Gmail contacts but the company has decided to remove support for Gmail completely. The war that Google started appears to have been finished by Facebook, but there doesn't appear to be a winner. Google's goal was to get access to Facebook's data, but it did not achieve this. Facebook, on the other hand, has made it very difficult for Gmail users to add their friends (read: they have to do it manually). As we've said before, while normally the user wins when two giants compete, this particular slew of bickering has led to a loss for everyone, including the consumer.