Correct word-count of a LaTeX document

I use texcount. The webpage has a Perl script to download (and a manual).

It will include tex files that are included (\input or \include) in the document (see -inc), supports macros, and has many other nice features.

When following included files you will get detail about each separate file as well as a total. For example here is the total output for a 12 page document of mine:

TOTAL COUNT
Files: 20
Words in text: 4188
Words in headers: 26
Words in float captions: 404
Number of headers: 12
Number of floats: 7
Number of math inlines: 85
Number of math displayed: 19

If you're only interested in the total, use the -total argument.

I went with icio's comment and did a word-count on the pdf itself by piping the output of pdftotext to wc:

pdftotext file.pdf - | wc - w 

latex file.tex
dvips -o - file.dvi | ps2ascii | wc -w

should give you a fairly accurate word count.