Here is a great introduction to Ripple:
https://ripple.com/wiki/Introduction_to_Ripple_for_BitcoinersWith an existing understanding of Bitcoin, it should help make the system clear.
Ripple is misunderstood, largely due to the efforts of a reputed scammer known as TradeFortress:
https://www.google.com/search?q=tradefortressHis attack site, ripplescam.org, is inaccurate and outdated---yet quoted daily. He had vested interest in attacking the system; it threatened his centralized ventures. Many lost money by trusting him over Ripple.
Ripple is a great long term investment. It is the most mature next gen platform, well funded, and delivers much needed features that benefit all currencies. As with Bitcoin, understanding will come with time. Ripple is not a threat to Bitcoin; it is complementary. Every day it is receiving more and more validation, especially from newcomer currencies which seek to address the same problems that Ripple has led focus on.
Ripple Contracts are the most exciting thing that I know of on the crypto currency horizon:
https://ripple.com/wiki/Contracts#Example_ContractsNew money will be entering the crypto currency markets in 2014, and I believe Ripple also has the greatest potential to interest traditional institutional investors.