Apparently Content Isn't King at least not anymore!

I know the statement in the title is pretty harsh and a lot of people may be upset with it but I have a story I would like to share and get some feed back on.

I have been working my butt off day and night since I've been laid off, researching topics to write on, writing 500 word article's and searching for keywords that are worth fighting for that think I might have a chance getting a good position in the serp's for.

I have one particular article that targets a keyword that get's a few hundred searches a day and the market is hungry to buy. When I seen this article was ranking well off the bat I decided to put a little more focus on it than usual. I worked on pushing the article to Google page1 for weeks and I finally made it. Yesterday my article reached the #10 spot for the keyword, I know that may not be the best but it shows progress.

When I woke up today my article was pushed back to the first spot on page two and a site that had zero PR, no content at all, zero back-links according to yahoo and google appeared out of nowhere and took my #10 spot.

Being bumped is no big deal because it happens but being bumped by a site that shouldn't even be indexed makes me think why am I working so hard to write unique content when site's that have no content at all can appear out of nowhere. What am I doing wrong, better yet what are they doing right? This is not the first time I've seen this happen.

What I want to know is how is this possible? I checked the on and off page optimization of this site and it is dirt, not optimized in the the least bit.

I don't expect anyone to have an answer to how these types of sites do that, I just wanted to vent because it seems unfair.