SkyDrive's policy changed. You now have 7GB free instead of 25...unless you used skydrive before the change, you now must be seeing this at the very first screen after you logged into your account.
To roll it back & if you're lucky enough go to Manage Storage > Free Upgrade 25GB. If this isn't available for you, then you obviously haven't uploaded anything to your skydrive before 30th of April.
SkyDrive will be a useful cloud service in the near future, many options such as syncing between different devices will be available...
Forgot to mention that command prompt will be also available.
Cheers.
