The command-history meme seems to have finally died a death (or maybe Im not reading in the right places).

One thing I couldn't help to notice was that the most common two commands for virtually everyone were cd and—usually right behind it—ls.

I'd wager that often, the ls follows straight on from the cd.

For some time at work, I've had the following in my ~/.bashrc: 

cd() {
	builtin cd $@ && ls -lhrt
}

This might well break some things, I'm not sure, but it's saved me a bit of typing.