Here is a list of tokens available for use in emails as of September 19, 2013:
{{campaign.description}}
{{campaign.id}}
{{campaign.name}}
{{company.Account Owner Email Address}}
{{company.Account Owner First Name}}
{{company.Account Owner Last Name}}
{{company.Active}}
{{company.Annual Revenue}}
{{company.Billing Address}}
{{company.Billing City}}
{{company.Billing Country}}
{{company.Billing Postal Code}}
{{company.Billing State}}
{{company.Company Name}}
{{company.Company Notes}}
{{company.Customer Priority}}
{{company.Industry}}
{{company.Main Phone}}
{{company.Marketo Data.com Id}}
{{company.Marketo Data.com Status}}
{{company.Num Employees}}
{{company.Number of Locations (A)}}
{{company.Parent Company Name}}
{{company.SFDC Account Num}}
{{company.SFDC Type}}
{{company.SIC Code}}
{{company.Site}}
{{company.SLA Expiration Date}}
{{company.SLA Serial Number}}
{{company.SLA}}
{{company.Upsell Opportunity}}
{{company.Website}}
{{lead.Acquisition Date}}
{{lead.Acquisition Program Name}}
{{lead.Acquisition Program}}
{{lead.Address}}
{{lead.Anonymous IP}}
{{lead.Black Listed}}
{{lead.Came from Email 1}}
{{lead.Came from Email 2}}
{{lead.Checkbox 1}}
{{lead.Checkbox 2}}
{{lead.Checkbox 3}}
{{lead.City}}
{{lead.Country}}
{{lead.Created At}}
{{lead.Current Generator(s)}}
{{lead.Date of Birth}}
{{lead.Department}}
{{lead.Do Not Call Reason}}
{{lead.Do Not Call}}
{{lead.Email Address}}
{{lead.Email Bounced Date}}
{{lead.Email Bounced Reason}}
{{lead.Email Invalid Cause}}
{{lead.Email Invalid}}
{{lead.Email Suspended At}}
{{lead.Email Suspended Cause}}
{{lead.Email Suspended}}
{{lead.Fancy MKTO Checkbox}}
{{lead.Fancy Thing}}
{{lead.Favorite Animal (L)}}
{{lead.Favorite Animal}}
{{lead.Fax Number}}
{{lead.First Name}}
{{lead.Full Name}}
{{lead.Hide Date}}
{{lead.Inferred City}}
{{lead.Inferred Company}}
{{lead.Inferred Country}}
{{lead.Inferred Metropolitan Area}}
{{lead.Inferred Phone Area Code}}
{{lead.Inferred Postal Code}}
{{lead.Inferred State Region}}
{{lead.Is Anonymous}}
{{lead.Is Customer}}
{{lead.Is Partner}}
{{lead.Job Title}}
{{lead.Languages}}
{{lead.Last Interesting Moment Date}}
{{lead.Last Interesting Moment Desc}}
{{lead.Last Interesting Moment Source}}
{{lead.Last Interesting Moment Type}}
{{lead.Last Name}}
{{lead.Lead Owner Email Address}}
{{lead.Lead Owner First Name}}
{{lead.Lead Owner Job Title}}
{{lead.Lead Owner Last Name}}
{{lead.Lead Owner Phone Number}}
{{lead.Lead Partition}}
{{lead.Lead Rating}}
{{lead.Lead Score}}
{{lead.Lead Source}}
{{lead.Lead Status}}
{{lead.Level}}
{{lead.Marketing Suspended}}
{{lead.Marketo Data.com Id}}
{{lead.Marketo Data.com Status}}
{{lead.Marketo Social Facebook Display Name}}
{{lead.Marketo Social Facebook Id}}
{{lead.Marketo Social Facebook Photo URL}}
{{lead.Marketo Social Facebook Profile URL}}
{{lead.Marketo Social Facebook Reach}}
{{lead.Marketo Social Facebook Referred Enrollments}}
{{lead.Marketo Social Facebook Referred Visits}}
{{lead.Marketo Social Gender}}
{{lead.Marketo Social Last Referred Enrollment}}
{{lead.Marketo Social Last Referred Visit}}
{{lead.Marketo Social LinkedIn Display Name}}
{{lead.Marketo Social LinkedIn Id}}
{{lead.Marketo Social LinkedIn Photo URL}}
{{lead.Marketo Social LinkedIn Profile URL}}
{{lead.Marketo Social LinkedIn Reach}}
{{lead.Marketo Social LinkedIn Referred Enrollments}}
{{lead.Marketo Social LinkedIn Referred Visits}}
{{lead.Marketo Social Syndication Id}}
{{lead.Marketo Social Total Referred Enrollments}}
{{lead.Marketo Social Total Referred Visits}}
{{lead.Marketo Social Twitter Display Name}}
{{lead.Marketo Social Twitter Id}}
{{lead.Marketo Social Twitter Photo URL}}
{{lead.Marketo Social Twitter Profile URL}}
{{lead.Marketo Social Twitter Reach}}
{{lead.Marketo Social Twitter Referred Enrollments}}
{{lead.Marketo Social Twitter Referred Visits}}
{{lead.Middle Name}}
{{lead.Mobile Phone Number}}
{{lead.MSIContactId}}
{{lead.Number of Locations}}
{{lead.Number of Optys}}
{{lead.Original Referrer}}
{{lead.Original Search Engine}}
{{lead.Original Search Phrase}}
{{lead.Original Source Info}}
{{lead.Original Source Type}}
{{lead.Person Notes}}
{{lead.Phone Number}}
{{lead.PickList Fun}}
{{lead.PickList Test 1}}
{{lead.PickList Test 2}}
{{lead.Postal Code}}
{{lead.Primary}}
{{lead.Priority}}
{{lead.Product Interest}}
{{lead.Registration Source Info}}
{{lead.Registration Source Type}}
{{lead.Relative Score}}
{{lead.Relative Urgency}}
{{lead.Role}}
{{lead.Sales Insight}}
{{lead.Salutation}}
{{lead.SFDC Campaigns}}
{{lead.SFDC Created Date}}
{{lead.SFDC Id}}
{{lead.SFDC Is Deleted}}
{{lead.SFDC Type}}
{{lead.SIC Code (L)}}
{{lead.State}}
{{lead.Total Opty Amount}}
{{lead.Total Opty Expected Revenue}}
{{lead.Unsubscribed Reason}}
{{lead.Unsubscribed}}
{{lead.Updated At}}
{{lead.Urgency}}
{{member.registration code}}
{{member.webinar url}}
{{social.Promo Code}}
{{social.Share Url}}
{{social.Social Email}}
{{SP_Send_Alert_Info}}
{{system.dateTime}}
{{system.date}}
{{system.forwardToFriendLink}}
{{system.munchkinId}}
{{system.time}}
{{system.unsubscribeLink}}
{{system.viewAsWebpageLink}}
{{trigger.name}}
{{trigger.trigger name}}
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