I really like Dyalog. I paid for the personal license before they made it free, but then when I thought about developing things for fun, and possibly commercial reasons, the licensing put me off. I still play with Dyalog, but J is the better fit for my needs right now. I am glad Roger Hui is on board, and I hope it does the same thing J did, and open source the code. I have a fondness for the characters in APL for no real objective reason. Maybe my love of symbols to make things concise and in one eyeful.