Where is the simple Save to gone in File?

There is no Save in Lightroom (the cloud version as well as the Classic version). All changes are immediately and automatically saved to the database that keeps track of all your edits and sent to the cloud for the cloud version. You can export images from Lightroom and that will generate external copies in the format and size you specify and with all the edits applied.

It is now File >>Export which has lots of new options in Lightroom v3. Many customers requested these. See if my YouTube video helps.

The New Export Dialog in Lightroom for Saving & Sharing Photos