In an obvious attempt to lure them users of DropBox to turn to the Cloud storage service OneDrive, Microsoft gives all customers of Dropbox 100GB free storage for one year.
To get the GB donations, visit this page to sign in to OneDrive and then verify it account your Dropbox.
The offer appears to be working globally.
Please note that OneDrive already offers 15GB free storage, 2GB in addition to Dropbox.