Here it goes ...
Progress V9 is ancient - in it's nucleus it's more than 10 year old technology, whereas OpenEdge 10 is the latest (state-of-the-art) technology. How the product has evolved over the last 10 years is beyond the scope of this forum, IMHO.
Pls, don't get mad at me, but your question, to me, sounds like the same if somebody would ask me "What is the difference between Windows Vista and Windows ME?". My answer would be - dump Windows ME, get rid of it as soon as you can!
Regards, RealHeavyDude.