Last month I posted about unlimited cloud storage for your photos (with 2048px limit) and videos by Google. If you want to get full-size backups of your photos then you had only 1 GB. Now the storage space has been increased to 5 GB, in addition to unlimited free storage at 2048px.
When you run out of Google Drive storage quota Google will automatically switch to storing photos at standard size.
To give it a try, simply turn on Instant Upload on your Google+ app in your phone and start taking pictures: photos you shoot will be saved to a private album on Google+.