Pros
This is a public interest organization that works on behalf of the consumer. So you'll know that your work is almost always fighting for "the little guy," something that's sorely needed. You are surrounded by bright people and there are a lot of opportunities for growth, depending on what you want to do and resources available. Additionally, you will have the opportunity to learn about tech policy in the areas of telecommunications and intellectual property. The staff are incredibly valuable resources for those who want to pursue a career in policy.
Cons
Public interest organizations don't always pay the best and sometimes the work can be a frustrating experience. A lot of the work done at the organization is in order to advocate before Congress or a federal agency like the Federal Communications Commission. Given that Congress is not passing much legislation these days and government agencies can move slowly, it's not always the most rewarding experience in terms of immediate gratification.