Seth Godin has a great definition of what an architect is in his blog here. Here's the description:
Architects don't manufacture nails, assemble windows or chop down trees. Instead, they take existing components and assemble them in interesting and important ways.
He goes on to say that:
...intentionally building a structure and a strategy and a position, not focusing your energy on the mechanics, because mechanics alone are insufficient. Just as you can't build a class A office building with nothing but a skilled carpenter, you can't build a business for the ages that merely puts widgets into boxes.
I like this because for me this is absolutely the essence of what an architect does, take existing components and put them together in new and interesting ways. That's exactly what Tim Berners-Lee did when he created the web. The key skill is not to get bogged down in the detail but to maintain the big picture of whatever it is you are doing. It applies equally to IT systems just as much as it does to buildings.