I have today added the ability to have your forum in Spanish.
To switch your profile to Spanish, click the EDIT button next to your name at the top of the screen and you will find Spanish in the drop down list, select it and then click SAVE at the bottom of the page and go to whereever you wish and all the system wide text will be in Spanish.
Clearly, someone else did this translation for us, so if you find any errors, then please let me know.