The latest scoop from the SharePoint Conference 2014 is that Microsoft has increased the storage limit for your Office 365 SharePoint Online sites.
Now your OneDrive for Business and Team Sites site collections are allowed to expand up to 1 TB in size. This is now all controlled by your Office 365 tenant administrators from the SharePoint Online Administration Center.
To add to this Microsoft has stated that for your entire tenant, there is no limit to the amount you can expand.
Keep in mind that you still have to pay a cost per extra gigabyte (GB) per month on top of the allotted amount for your subscription.
For more information, see Mark Kashman’s post on the Microsoft Office Blog.