Dropbox - Current options
50 GB ($99.00 USD per year) - 100 GB ($199.00 USD per year)
Google Storage - Current Options
20 GB ($5.00 USD per year) - 80 GB ($20.00 USD per year) - 200 GB ($50.00 USD per year) - 400 GB ($100.00 USD per year) - 1 TB ($256.00 USD per year) -
I hope their prices stay that low.
That said, with Dropbox's versioning of files, I can see Dropbox arguing each Gb you have there can really be much many more Gbs than what you seem to pay for.
It will be interesting to see Google's features. What I value most from dropbox is the versioning and the relatively seamless integration into the operating system.
The interface seems different, the dropbox versioning appears to part of its file system, the google versioning as part of the application.
So for me, dropbox versions some blobs (truecrypt volumes) that it's not clear that google could version, unless they add a different interface to google drive (and I sure hope they do.)
Not to mention that it has the office capability (arguably better from my POV), too.
It's $0.33 per GB-month for all the Google storage tiers. This is the best you'll find pretty much anywhere on the Internet.