While I don't know much about APL in specific, I do know the answer to that for COBOL - the pie-in-the-sky goal is to migrate, but, because it's the least-risk solution, the trend is to increase utilization.

Part of that is because of the hardware limitations. Until IBM started putting Linux on mainframes, there was no (good) way to get the sheer power of a mainframe without programming in COBOL. Now, there is, but it's extremely new. Companies like MasterCard, Motorola, and the like aren't going to migrate simply because it's out there. It could be the next best thing, or just the "Next Best Thing"(tm). When your $100 Billion business depends on the decision and what you have is how you got to B$100, you tend to be a little biased to the status quo. And, frankly, I don't blame them.

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We are the carpenters and bricklayers of the Information Age.

Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.

Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.