By using Google translator, it will not necessary increase your ranking, what it might do is increase the presence of your site in other parts of the world where English is not the first language. So if your site and products are in English there will be no major difference One of the disadvantages of using Google translator is its translated using a program, and most of the times, it produces text that is not grammatically correct, You may achieve the translation but will it give a good image of your site when the content is not grammatically translated. I would recommend if you are a looking to target foreign countries, i would advise to use a professional translator, that translates the content of your site in to the language you want, and then do SEO on those pages.
I'd actually recommend using the Wibiya Toolbar. It adds a TON of functionality to your site, and has many more features than just a translation service. If you want to see the translator on the toolbar in action, you can visit my site in my signature, and if you like it just go to http://www.wibiya.com/
I have tested Google translator, but the translation is so bad that I removed it, it will scare visitors away when they read that crap. Oh, and it's NO GOOD for SEO...
It allows users to get an idea of what the site is about in their own language. Unfortunately, unless you have a *very* simple text, the translation is horrible, I experimented with several languages and decided that I did not want that kind of language murdering on my sites. It does NOT provide anything regarding SEO, as it is "on the fly" translation. You will *not* get any kind of SEO boost with it. And for those who think machine translation is a good thing for their site, I would like to invite you to read my last post on how to be smart and Stinky #1 locally on the Internet with machine translation!