Show a Picture of your Content

B2B buyers are inherently risk averse. If you're providing a white paper for example, show a nice picture of the front page or first page of the paper. If you're providing some type of eBook show the cover of the eBook. If you do a good job of conveying the value of the content the subscriber is less likely to give you their personal email (gmail, yahoo, etc.) and give you their corporate email instead.