I am developing an asp.net application. The user wants the site should get a high ranking in the search engines. I asked him for some keywords, which I would have included in the metatags. Now, he has given me keywords in a 52 page .doc document. The total no of keywords must be around 3000. Is it prudent to add all those keywords in the metatags. Also, is there a way to put all the keywords on a seperate file and include it into the meta tag with #include directive. What is the best way?
That many keywords would be a waste. Meta Tags are virtually worthless anyways so what your client wants done will only hurt them in terms of server performance and page loading times for virtually no benefit.
Thinking through which meta keywords and descriptions you want on each page is a useful discipline because it makes you consider which search phrases you are targeting in your content on every page, and helps to guide the structure of your site.