When it comes to emails, mistakes happen all the time. But very rarely do they involve former Vice Presidents of the United States. So it was quite surprising to see CNN.com inadvertently reveal the email address of Al and Tipper Gore Tuesday afternoon. "Our intention was to keep the email address confidential, and CNN corrected the online post as soon as we discovered the error," a CNN spokesperson told WebNewser. So what happened? CNN.com today posted a story about Al and Tipper Gore's separation. The story included a link to a PDF of the email the Gores sent to friends....