Besides a fresher appearance there's improved organization and navigation. There are high-level views of the products (available on the front page, with tabs along the bottom for each product) and more detailed pages on each (FR and FD), with product tours, benefits, faqs, and much more. This breakdown of high-level and detail views applies as well to discussions of the Air Enterprise Dashboard and their Services (consulting, training, etc.)
Through the updated web site you can also learn about many other resources available, including articles, videos, and blogs by them and others; product docs, screenshots, FAQs and more; info on customers and free/paid support; community tool contributions, and lots more.
The folks behind FusionReactor/FusionDebug are really great. They're very open to communications and always welcome (and act effectively on) feedback. I've been a long-time fan, so much that I work with them directly on doing training and consulting based on their products (while remaining an independent consultant.) It's their very openness and willingness to listen to feedback that brought me to working with them more and more closely over the years. I'm glad to help others take notice of the company and their great products.