We are working on getting Dutch ready. Hopefully, it won't be too much longer. Regarding new beta languages, unfortunately, we will not be adding them. If you want Thai added, the requirements for supported languages will have to be met and it will then be added. You can find more details here - http://www.lingq.com/newlanguage/.
Oh, ok. Then all I have to do is mail you the material, and provided it passes your quality inspection, Thai will be added?
@Wulfgar - That is correct provided we don't encounter major technical issues related to implementing Thai.
Yes. And in fact Mark has informed me that Thai is too difficult to implement.
What's the advantage gained in promoting a language to official status? I've enjoyed learning some Dutch as part of the beta languages, and it didn't feel different to the official languages to me. Is the difference just that beta languages might not have sufficient content yet & haven't been checked for quality control?
Also, I guess official languages have to be tested in the mobile apps & against the LingQ API? In that case I can see why Thai might be difficult to implement.
According to Steve Kaufmann, any issues related to official languages will be resolved whereas that is not the case for beta. Moreover, Lingq usually provides content for official languages so the lesson series "Who is she?", which is available in all the official languages, will presumably also be available in Dutch.