Hi guys and girls, I have a project of a site in English and Spanish in mind but I have concerns about SEO.
Do you think it’s better to have both languages in the same site, or 2 sites (i.e. subdomains), one for each language?
My feeling is that, as all the important keywords are very different in English and Spanish, one single site would be less relevant for the keywords in each language than one site for each language, but the amount of content would be split in half…
Thinking a bit more about that… So you think the “strenght” of having a two domains with keywords relevant for each language is not worth it, and that it’s better to have a single site with a domain containing the keyword in one of the languages, right?
Google is perfectly capable of figuring out that a site that refers to ‘car’ in its English pages, ‘voiture’ in its French pages, ‘coche’ in its Spanish pages (etc) is all about the same thing. If your site structure is set up properly, it is unlikely to make any tangible difference whether you have:
domain.com, domain.fr, domain.es
domain.com/en, domain.com/fr, domain.com/es
en.domain.com, fr.domain.com, de.domain.com
If you can register all of the relevant domains, I would go for the first one, because it may help localised searches, and it will make it easier for people to remember and type the URL.
I would generally try to avoid the last one, unless you are aiming at a relatively technical and savvy audience, because there is a high chance of them typing the URL wrong. If you do go down that road, make sure you set a rewrite rule that strips an errant “www.” off the front!
Well, I guess I should have figured that out 
Thanks!