You probably have tons of data that needs to be saved and stored somewhere for the long-term. Not your everyday files, but huge, important files that relentlessly keep growing, like your video and photo collections. That's where Google Cloud Storage Nearline comes in.
The service is much like Amazon Glacier, Amazon's low-cost storage service meant for data archiving and online backup, which also costs $0.01 per gigabyte. Where Nearline Storage differs, however, is that when you need to retrieve data from Amazon's Glacier servers, it could take several hours to even days until you can access it, while Nearline makes the data immediately available, with 3-second response times.
Nearline also has many of the downsides Glacier does, though. Because the service is meant primarily as a backup and archiving tool (data insurance, more or less)--and not for constantly accessing the data stored on Nearline--there's a cost to retrieve your data (another $0.01 per GB) and also an early deletion fee if you delete data if it's not stored for at least 30 days.
For most people, unlimited backup services like Crashplan and Backblaze are easier to understand: There's a set $5 a month cost for backing up your most important folders and connected drives. With Glacier and Nearline, the cost may be super cheap, but you have to calculate that.
Still, I think these services can complement each other. An unlimited backup service saves your day to day files in case of hard drive crashes or mistakenly deleted files. Archival storage services are for creating an additional backup and saving files for the long term (I'd also save them on Blu-rays or other disks). Redundancy is key when it comes to backing up.
There's one more thing when it comes to Google Nearline. While there are quite a few Amazon Glacier third-party tools to access and manage your Glacier files, there aren't any yet that I know of for Nearline. Google does say, however, that Nearline will be integrated with popular backup and storage providers such as Veritas/Symantic, NetApp, Iron Mountain, and Geminare. The emphasis on this cloud platform tool is for business and enterprise organizations to manage a ton of data, but video professionals and other individuals might perk up at the 1 penny per gigabyte pricing too.