Yogi Berra said "Nobody goes there anymore. It's too crowded." The App Store is great, because there are so many apps, but that's also what makes it a problem. It's hard to find good apps, and even harder for good app developers to stand out.
Some developers have turned to the Dark Side and paid for installs and reviews. This gives them a temporary boost in the rankings, and makes it look like the app is popular for a reason. Usually the fake reviews can be weeded out, but only if the consumer bothers to do some research... most don't, especially at $0.99 per app.
As a developer, I've been a victim of fake reviews. A competitor wrote bad reviews of my app and positive reviews of his. It was pretty blatant, but Apple didn't do much about it. I reached out directly and convinced him to change his ways, and he removed the bad reviews. But that's small potatoes. Now there are entire businesses whose sole purpose is to "sell" positive reviews in the thousands and even tens of thousands.
Apple has had enough, and, as TechCrunch reports, has started to remove those reviews on a grand scale. They still haven't removed the developers' accounts, but it's safe to say they are on probation. The App Store can be a nice source of revenue. Apple has made it easy for software developers to sell apps without the headaches of distribution. If we can't police ourselves, it's time for Apple to do so, to keep the integrity of the ecosystem. After all, it could be worse. Google Play is pretty much a free-for-all!