This is almost common knowledge in the startup world, and yet, even I (who don't cover any startup releases on swombat.com) still get emails from people looking to get some coverage for their startup's new product.
Clearly showing that you understand that a journalist doesn't just exist to publicize you is one of the fastest routes to his or her heart. It’s literally the difference between drunkenly hitting on someone in a club and taking him/her on multiple dates to the restaurant you can’t afford. Hell, you'd be unlikely to start a sales pitch without knowing your customer, or begin discussions with an investor without finding out exactly what they were interested in -- so why treat the media differently?
The closest relationships journalists build are with people who can provide long-term value to them by offering something that isn't just self-promotion. Conversely, these tend to be the names you see cropping up again and again in the media.
The age of the one-way exchange with journalists is over. Even Apple cultivates strong, two-way relationships with journalists and bloggers.
Every bit of (worthwhile) news coverage I've had for my startups has come out of a valid, two-way exchange. Sure, there are "news organisations" that will republish press releases without thinking twice - but nobody reads those anymore.
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