I agree with apostrophe. Intro pages are for the most part "exit" pages in your analytics.
I think maybe it would be nice to know why the client asked for this. If their ‘means to an end’ was to simply offer a quick introduction to the whys and wherefores of what they’re all about, a ‘custom-page’ like apostrophe mentioned, with some sort of jQuery slider, would be an apt solution to their request. Showcasing of their warez and services could be accomplished in a very slick manner, yet marriage to the basic wordpress theme could still be maintained.
(and that domain name they snatched is outstanding.)
have you done anything yet with the redesign/development? I noticed from the source for the url that it’s still an ancient table-based design.