We use multiple languages on our site Farm Equipment-Heavy Equipment-Construction-Grounds Care-Material Handling-ELS. When we first went to this format 2 years ago we tried using seperate domains for each language, since these were new domains our efforts made very little impact into the search marketing. After 2 months we brought everything back to the Equipment Locator domain and used directories to seperate the language groups. This allowed us to take advantage of our domain history and popularity to increase our traffic on the other languages.