This is an important step for Western Digital as its software has been traditionally locked to its own devices, but the company recognizes that supporting a leading 3rd party storage system can benefit WD users, and ultimately WD itself. After all, the cloud may provide virtually unlimited storage, but local storage is still king when it comes to how convenient and fast this access is. For example, web uploads often have a relatively low limit in how big each files can be (300MB on Dropbox). When that happens, it is possible to upload a file to the WD box, and share a direct link to it.
WD 2go is a free application that run on iOS and Android, and now we are wondering if other cloud storage systems such as Amazon S3 or Box will be integrated in the future.