Note: This review used to discuss the free chat-roulette aspect of Verbling. It was a genius idea, and they used it to launch their site, but sadly this feature that made them so famous was removed, and now it's a site based around paid lessons, although it does have some limited free chat room functionality.
I had to remove my long review of their old and excellent chat-roulette feature now that it's not active.
I'll come back to this review and update it to reflect their current site asap, but there are many sites out there that offer paid lessons, so I'm not sure why Verbling removed what made them famous and unique. For now, I'd highly recommend you go to italki for a better way of finding free and affordable teachers of all languages. Here is my detailed and up to date review of italki.