Microsoft has revamped and extended its SkyDrive service to deliver simpler, more straightforward cross-platform data storage and file synchronisation.

Perhaps the most immediately obvious change is the Dropbox-like addition of a new folder to your file system, which then represents your online account. Drag and drop files or folders here and they’ll be synchronised to your account and other devices. Similarly, if you rename or delete a file on your phone, say, the change will be synced to your PC right away.

You also get a new Fetch system, which is effectively a form of simple remote access: if you’ve forgotten some important file on your home PC then you’ll be able to access it via SkyDrive.com.

All your file syncing now happens in the main SkyDrive folder

Improved smartphone support sees you now able to delete, rename and move SkyDrive files, as well as take greater control over the system’s file sharing options, from Windows Phone and the iPhone. A new iPad app delivers the same capabilities, and Mac users can now manage their entire SkyDrive account using Finder (which means any application which writes to the file system can now also take advantage of your SkyDrive account).

Microsoft has also reorganised its storage allowances. The headline news here isn’t so great, as the standard capacity now drops from 25GB to 7GB. However, you can now synchronise using the full 7GB (the previous limit was 5GB), and the desktop preview can now handle files up to 2GB in size (though the apps and web interface still currently limit you to 300MB).

If you’re still unhappy about that, the good news is that, if you were using more than 4GB of storage as of April 1st then Microsoft should have automatically kept your previous 25GB limit. And if you had any files uploaded to SkyDrive at all as of April 22nd then you can also manually opt in to keep your 25GB storage allocation (though you’ll need to do it in a hurry; Microsoft say this offer is for a “limited time only”).

But if all else fails then there’s always the paid option: you can add 20GB for an annual $10, 50GB for $25, or 100GB for $50 a year, which seems like reasonable value to us.