No sooner than Microsoft upgraded its OneDrive offerings for both regular Microsoft account holders with 15GB free cloud storage and Office 365 subscribers with 1TB of cloud storage, Google trumped that with the launch of Google Drive for Work premium service offering with unlimited storage space!
Google was the first to offer 15GB of free storage space and that still remains along with lucrative storage upgrades for just a meager sum. However, Google Drive for Work brings about a bunch of other business-class features for just US$10/user/month. To further clarify this, Google treats each "user" as a distinct email address; as such one real-world user can have multiple email inboxes. There's a catch though; if you subscribe to less than 5 "users", Google Drive for Work only offers 1TB per "user". So if you're really out to just get unlimited storage space, you'll need to subscribe to at least 5 "users" that comes at a cost of US$50 per month. At this rate, it's even more competitive than Dropbox's US$15 per user which offers nothing but raw storage space.
So what else do you get with this new service? Essentially, Drive for Work builds upon the existing Google Apps for Business offering with the Google Vault service, but adds a whole lot more storage, which Google says is now encrypted and not only on the servers, but also when data is transmitted from your device to Google Drive and in transit between their data centers. In addition to enterprise class security and compliance, you can also upload and share files sized up to 5TB each! For a complete list of other controls and services that Google Drive for Work (which is inclusive of Google Apps for Business and Google Vault), you can check this link.
On a side note, a new enhancement to Google Drive in general will now allow all Drive users to open and edit documents in their native format using Office Compatibility mode in Docs, Sheets and Slides on Android and Chrome browsers. That's great news when you need to touch up documents in their native format (such as those in Microsoft Office) and not having to convert them back and forth or purchase software specifically to gain editing controls.