If you are designing promotion email for a client, the regular license:
advertising and promotional projects, including printed materials, product packaging, presentations, film and video presentations, commercials, catalogues, brochures, promotional greeting cards and promotional postcards (ie. not for resale or license);
If you are making a website where people come and pick e-cards to send out, the extended license:
you may not ... use the Content in design template applications intended for resale, whether on-line or not, including, without limitation, website templates, Flash templates, business card templates, electronic greeting card templates, and brochure design templates;