S4S includes a custom xDB contact facet which allows additional data to be stored against a Sitecore contact. By using the included S4S rules personalised content can be configured based on the values stored in the facet. The facet currently supports the storing of data in a dictionary of string values and also the storing of profile key values for a specific profile.
The S4S Personalization Salesforce package enables values set in Salesforce contacts or leads to be automatically synchronized into the corresponding xDB contact's facet. This enables content in Sitecore to be displayed to a visitor based on current values stored in Salesforce.
Additionally, the package can be used to set particular profile keys for specific profiles within Salesforce which will be synchronized to the corresponding xDB contact. Again personalized content in Sitecore can be presented to a visitor based on the profile keys saved in Salesforce.