@eric, it depends on what you want to do with those contact details. If it is just a block of unstructured data that you want to eyeball whenever you reference the customers then fine.

If you want to integrate it with separate telephone dialling systems and email targetting systems then I'd normalise it out.

Ditto security. Separation of data to support different contact methods allows me to assign different security based on the sensitivity of the data. Email addresses tend to be less sensitive than telephone numbers.

Frankly it is so easy to normalise your example that it simply wouldn't occur to me to put it in an EAV. You have disciplined data and you are going to store a lot of it if it is a contact system. I regard EAV as an option of last resort, not a starting point to be optimised later.

The medical example early in this thread is an example where EAV genuinely is useful. Once you get past 40 the sheer number of things that can go wrong with a human body becomes horribly apparent and I sooner try and normalise the human body than represent its ailments in an EAV form.