Yes, regularly used in our house, usually to follow up something in the news that has piqued the interest. I recently watched a TV series where someone turns to camera and says “google it!” and almost inevitably that led to ‘look it up on Wikipedia’. It would be missed were it not be available.
Although, as you of course are aware, there are issues out there with the fact that anyone can alter or create content on Wikipedia as far as I know.
I don’t use it as much as I once did, but I still use it, and still donate when asked (though not huge amounts, I confess).
As others point out, it’s freely edited and can be subverted: but it’s often a good jumping-off point for finding other sites and key-words.
With some of the new types of courses being offered by various educational institutions that require students to mainly learn the subject by using the internet then I wonder what would happen if Wikipedia did vanish or become subscription only.