Pages offer a quick, real-time/instant view word count which is easy - and fun!
In Document Inspector (first icon on the left) click on third tab Info. Here you can see the word, line, paragraph, character and even graphics count for your document.
But this isn't all. If you click on your text and start dragging cursor to highlight a selection of text the Inspector gives you the count of all the elements - words etc. as you drag.
Being able to check word count (character count) is important in many ways.
In publishing it is one of the main methods of checking how much space needs to be allocated to copy within the pages of a publication. It is a means of coordinating work between editors, writers and production.
For writers, journalists and translators word count is often used as a valuation tool - you get paid by the word.
Please also read this article, published later on I work in Pages:
Word count in Pages: use two Inspectors
Read more in my new book 'iWork for Mac OSX Cookbook' (2012). Follow me on Twitter at iworkinpages, like my page I Work in Pages on Facebook and add me to your circles on Google+.