Does it actually matter that much in Java? In Java, a collection of objects is already a collection of pointers, so wouldn't we get a fair number of cache misses anyway? Or does the JVM have some cool mechanism to minimize those?

With Java, and any other VM that doesn't specify an exact GC algorithm, it always depends.

IIRC the train algorithm used in some JVMs improves locality. Most GCs use a pointer-bump scheme anyways, leading to pretty good locality for objects that have been created together.

So yes, the JVM _may_ have some pretty cool mechanisms to minimize those. I would be also interested in G1s behavior and whether or not it improves locality somehow.

Some JVM implementations convert objects into value types if they are final POJOs e.g. Point with X/Y accessors, Azul does this I think, but most likely it won't work for list like structures.

I agree, the e-voting technology should be a lot more secure, but as long as they keep improving it, I don't see it as too big of a problem, but if they used the same technology in the states for example, I would be pretty worried. The influence Estonia has in the world is negligible compared the US, so if something was to go wrong, sure, it would be pretty bad, but compared to the same happening in a more influencial country, it would be pretty minor.