I play a [Vorinclex, Voice of Hunger](https://gatherer.wizards.com/Pages/Card/Details.aspx?name=Vorinclex%2C%20Voice%20of%20Hunger) commander deck casually with friends. If one of my opponents plays [Mind Control](https://gatherer.wizards.com/Pages/Card/Details.aspx?name=Mind%20Control) (or something similar) and takes control of Vorinclex, do the triggered abilities now benefit my opponent and hurt me? That is, does it help its controller or the owner?

Also, since my opponent tapped lands to play Mind Control while Vorinclex was still mine, I think the lands he tapped to cast Mind Control stays tapped next turn. Is my thinking here correct?