Just tried it out-- it's a neat concept. I wish the "free" version was more giving... I'll have to try more to see if it's something I'd want to pay for. Overall, it seems fairly useful.
Following up-- for anyone that wants to try it, if you use a referral link (plenty on Youtube if you look for lingq reviews) you can get like 120 lingqs upon signing up. That's a much better trial.
So far I'm liking it.