I am using the following google shopping extension:
http://www.magentocommerce.com/magento-connect/google-content-api-for-shopping.html
This extension works great for me, but I want to add a new google content attribute, because I want to import a special product price for products too. Currently I can't mapping a special price because only the google content attribute "price" is selectable, but I need a seperate attribute for special prices. Hope you can help me :)
UPDATE: I have changed the config.xml of Google Shopping Extension and now the sale_price is also available for other countries then US. Product Synchronisation works, but I can't see the special price in google merchant center.
<sale_price translate="name">
<name>Sale Price</name>
<required>0</required>
<!--<country>US</country>-->
</sale_price>
<sale_price_effective_date_from translate="name">
<name>Sale Price Effective From Date</name>
<required>0</required>
<!--<country>US</country>-->
</sale_price_effective_date_from>
<sale_price_effective_date_to translate="name">
<name>Sale Price Effective To Date</name>
<required>0</required>
<!--<country>US</country>-->
</sale_price_effective_date_to>