Minecraft is written in Java.
> When will ... even more specialized medical/industrial/scientific software be available for android?
Presumably when the people buying the software begin to express an interest in moving to android. I'm not saying that it will happen, just that the software will be ported over, or new software written, when people start wanting it.
I don't think that anyone seriously believes that android is going to replace OS X and Windows on desktops, just that, as time goes on, people will be spending more and more time on tablets and smartphones and less on traditional desktops and laptops. I find it a bit sad, mostly because I refuse to believe that I'll ever be able to type as quickly on a tablet as I do on a keyboard.
Now, what you are talking about - computationally-intensive tasks that traditionally require workstations - Android does not perform nearly as well. But the people who really need that kind of processing power and can't satisfy it with a tablet, game console, or other home-oriented system are only a small segment of the overall market.
People don't shift platforms to do what they used to do on their old platform - they do it so they can use the new things on the new platform.
angry birds does not count
Why not? I've played more angry birds on my desktop computer (in Chrome) than any other game.
(Edit: lol - I'm guessing Angry Birds is was got me the downvotes?)