I am sure it was a blast, but it was NOT done "for fun" to amuse the engineering staff. Nor is it an effort at "home automation".
This is part of a marketing campaign not unlike the office depot "easy" button, except they've designed an actual button that sort-of works.
The point is to get people excited about the idea of a Netflix marathon and create some buzz among geeky subscribers. It doesn't matter how many people actually create or use "the button".
Well, I'm sure that was an excuse, but seriously. Do you honestly think the kind of geeks that'd do this are really that important to a company like Netflix these days? Maybe at the beginning...
If I had to attribute anything, it's more of a recruiting move. They want clever hacker geeks working for them. Maybe they are moving into home automation and this will be an interview question? I dunno how effective that is, though. I think someone just said, yeah, screw it, let's do it!
A little viral-ness doesn't hurt either. If it makes a dozen or so blogs today and reinforces the idea that Netflix is a service you cuddle down with in your den, that's not such a bad thing.
