Will I be able to save files online with the Office Web apps?
You'll have the option of saving files online, although you will have to sign up for a to take advantage of the cloud-based storage.
Will the Office 2010 Web apps be free?
Yes. Personal consumers will be able to access the Office 2010 Web apps free of charge using a Windows Live ID.
Why would I want to consider the PC-based Office 2010 instead of the Web apps?