Should entrepreneurs just give up on their app ideas, simply because Facebook could eventually clone them and crush them with a billion users? Of course not, and anybody who thinks that Facebook (or any other big company) cloning a startup's product spells Armageddon for that startup doesn't know what they're talking about.
Remember when Facebook tried to make a Foursquare competitor? How about the time it tried to make a Groupon competitor, and it went nowhere? The same is true of its Quora competitor (Facebook Questions) and even its Craigslist competitor (Facebook Marketplace).
I could go on and on, but the point is clear: a big company launching a clone can be scary, but it doesn't mean Armageddon. There are two other factors to consider: defensibility and vision.
