What is one strategy for effectively pitching to the media?

Assuming you've already identified the right media based on what your target prospects read and respect, get to know the publication and writers. Learn what they like, what they write about. In other words, the reporter is a prospective customer. You're not going to sell him or her a story unless you align your story with something they already care about.

Do your homework, make a pitch in context, and tell a customer-centric story.

I agree with both Elizabeth and Matt (especially his comment about knowing the pub and reporters) and would add a couple things. First, determine whether you're going to pitch trade media or general media. For trades, you can pitch 'softer' news such as product announcements and the like. Those pitches are tougher sells for general business media. In either case, you need to be sure your pitch is news and not simply a marketing message. Second, you need to be responsive. If you send out a news release, be sure to include contact information and then be sure to 1) be there to answer the phone or respond to email and 2) answer the phone and respond to email. If you're the PR person, be sure you have a company official or customer ready, willing and able to talk with a reporter. Reporters will take comments, confirmations, etc... from the PR person but much prefer connecting with the subject matter experts. Finally, it's about building relationships and it takes time, so be patient.