The only thing I can see stopping it is another cryptocurrency which accomplishes everything that Bitcoin does and more, only with a codebase so different that Bitcoin can not adopt these added desirable features.
May I ask how important you feel Turing completeness is in the scripting language?
I'm sorry, I do not have the technical knowledge to answer this question. Give me a few days and I may be able to give you an answer.
He is speaking about NXT and its future developments.