In a Google+ update (how very 2011), Google product manager Scott Johnston confirmed that the maximum size for a single file in Google Docs has been increased from 1GB to 10GB.
Google Docs only includes 1GB of free storage by default, so this is mostly relevant to users who have already paid for a storage upgrade (which starts from $US5 a year for 20GB). Documents created natively in Google Docs don't count towards that total, but imported documents do. As such, the change is potentially useful if you import a lot of video and picture-heavy documents.
[via Google Operating System]