Maybe this will be useful to understanding lifetimes: http://static.rust-lang.org/doc/0.8/tutorial-borrowed-ptr.ht...

As for the pointer dereferencing, perhaps putting the type there will make it clearer:

    [1, 2, 3].map(|x: &int| if *x > max { max = *x });

Now you can see that x isn't actually an int but a reference to one.

As for automatically derived traits, those are actually slightly more powerful macros implemented in the compiler itself. You can see it at rust/src/libsyntax/ext/*.

For default methods, you just put the code you want in the trait itself. Like so:

    trait Animal {
        fn sound(&self) -> ~str;
        fn make_sound(&self) {
            println(self.sound());
        }
    }

The make_sound method is what's called a default method. If you implemented that trait, at the very least you would have to define the sound method and if you wanted to, you could override the default make_sound method.

Macros are actually created with another macro called macro_rules. I'll defer to the tutorial for them: http://static.rust-lang.org/doc/0.8/tutorial-macros.html