It's all about building a relationship with these journalists and bloggers. You want them in your pocket long term. Ultimately, they are usually interested in the same things as you, which gives you a chance to connect on a deeper level and make an online friend. If you make a friend, then maybe they can even introduce you to their other journalist friends when the time is right. Ps: when you finally do send them your stuff, keep it short and make sure your visuals get the point off without them needing to read a description. Visual storytelling is huge. Remember: people don't like to read