You can now set three new email notification options in your salesforce.com connector. Click on the gear icon next to your connector’s name and expand the email settings to see the various options. If you are using Pardot’s notifications for prospect assignments, you will probably not want to enable salesforce.com’s. Otherwise your reps would get a notification from each. If you would prefer to use salesforce.com’s emails, simply disable the assignment notification by editing the email preference settings for your users.
salesforce.com Connector Settings
salesforce.com Email Notification Options