Magento – Google Shopping module that use Shopping Content API v2

This is in fact a great idea and there are already few implementations. There is a great article by Ashley Schroder.

Also there was some extension on Magento connect allowing importing configurable products from Google Spreadsheet.

Also there is an extension integrating MAGMI features with Google Spreadsheet into Magento admin here.

The idea of keeping the spreadsheet in an online editor application right in browser is overall good, it's just like the evolution wants it to be. I think many people agree that whole task of products data entry turns out much more technically problematic than it should be and this approach makes things easier. However there are many more issues making this routine (catalog entry) really problematic. For example the frustrating fact that "import format" is not similar to "export format" in Magento out of box, or thin things like related products, configurable, cross-selling links which are hard to figure how to do. So the important key point here is to keep it all-purpose, simple and consistent. Also ability of transferring in both directions (import/export) and supporting maximum fields is crucial.

Overall this is a big field where one can make things better - mixing technologies always gives great results.

See That Extension is developed by the MAGENTO.

So they mention on site like support up to 1.7.

As per My experience if they the Module is not override any core functionality then It will work in 1.8 as well as 1.9.

you can try to install in local machine If everything is working fine then you can use for your live site :)