Pardot users now have the option of providing email signature content that can be automatically included in newsletters and automated emails! Users can specify this by editing their user profile:
To include this signature information in an email, we’ve introduced two new email substitution tokens – %%user_html_signature%% and %%user_text_signature%%. These tokens will be replaced when the prospect receiving the email has an assigned user and the “Send from assigned user” checkbox is checked. If those conditions are not met or the user has no email signature content, the tokens will simply be removed and not replaced with anything.