Here are couple of options of how you can use the top portion of your email marketing campaign:

NordStrom uses two classics: Add NordStrom’s email to your adddress book and view in browser:

http://cesardonofrio.files.wordpress.com/2008/08/nordstrom.jpg

SmartBargains uses one main call to action (with the banner) and two other small offers:

http://cesardonofrio.files.wordpress.com/2008/08/smartbargainscom.jpg

The Scooter Store uses two calls to action, add to address book and view in bowser (maybe too much for my taste, but really powerful):

http://cesardonofrio.files.wordpress.com/2008/08/thescooterstore.jpg

Victoria’s Secrets uses just the main call to action and view in browser: 

http://cesardonofrio.files.wordpress.com/2008/08/victoria_s-secret.jpg

What is the best? Nordstorm is a classic, some cases The Scooter Store could be a good powerful one. And for other brands Victoria’s and SmartBargains will be a elegant solution.