Interesting idea, and I agree there's a lot more we could do to better support the social causes on-site vs. just the general domain redirects. We created this all in a weekend at the #hack4good hackathon in SF, so what you're seeing now is just the beginning.
Amy here, one of the creators. Great point, and there will be some self-reporting necessary here since we obviously don't have access to anyone's Google Analytics. If you have submitted domains through the site, please let us know how it's working for you! The referrer should show as domains4good.org. A/B testing the copy/design of the interstitial page before the redirect is also something we can test in the future to see what encourages people to stick around the longest. Thanks for the comments.
Amy Ziari, Pasta founder here. There are plenty of great agencies out there. The best list I know of is O'Dwyers. For example, its list of top tech PR agencies: http://www.odwyerpr.com/pr_firm_rankings/hightech.htm
"Top" is based on annual billings vs. quality, so the list is something you'd want to supplement with recommendations and research. Still, it's a healthy starting point.