Extra-terrestrial documentarians misinterpret everything and we howl with laughter. This may be a kids' show, but it's also one of the best things I've seen in a while.
The humor is quick-witted and understated, but not subtle; much is implied, but still obvious if you're paying attention. For characters with alien dialog, they end up with some actual depth. The dialog is amusing but not as clever as Minionese.
For family entertainment, Alien TV does an excellent job of skirting the line; there are some definite WTF moments to which stuffier viewers might object, but which I thought were hilarious and very well executed.
This show is clever, creative, accessible and broadly entertaining. Since I have a feeling that the show's creators are probably limited by expectations of their target audience, I'd love to see what they'd come up with for some more adult-oriented comedy.
I won't post any spoilers, even though that'd be difficult to achieve given the format. I will say that while the first episode is fun, the rest are progressively better. The series has an excellent arc.