Become genuinely interested in other people. Be a good listener. Encourage others to talk about themselves. Talk in terms of the other person's interest. Make the other person feel important - and do it sincerely. If you're wrong, admit it quickly and emphatically. Begin in a friendly way. Dramatize your ideas. Ask questions instead of giving direct orders.
In Tumblr's favor are the myriad options for posting, including Web, e-mail, iPhone app, phone call, desktop blogging apps, and more. Tumblr also has a certain design flair that isn't evident in Posterous, and certainly has more, and more interesting, themes to choose from. And, some may prefer Tumblr's clear separation of content types and multiple options for text editing. In Posterous' favor are its ease of posting via e-mail, and the especially clever auto-uploading and auto-formatting of attached media. If you post strictly audio or video files, your Posterous RSS feed can also act as a podcast feed. These advantages may appeal to users who focus on a lot of media, such as photographers, music bloggers, or podcasters. Posterous still has a fairly spartan design aesthetic, though the developers are working to address that with new themes and Tumblr compatibility. And some users may appreciate not thinking about content type so much as just getting it posted online