It's a huge concern. When a company starts hitting that $100M range, you're essentially worth a decent percentage of what Facebook is worth (maybe 5%). At tha

It's a huge concern. When a company starts hitting that $100M range, you're essentially worth a decent percentage of what Facebook is worth (maybe 5%). At that point, it starts making sense for Facebook to put a little work to competing with you and putting you out of business. These platforms can be good if you're willing to be unnoticed in the corner. However, if you find something highly worthwhile, your landlord can copy you and shut you out. If you're talking about a $50M buy, you have to be thinking that you'll be able to get at least triple out of that on such a risky purchase. And if a Facebook app is that worthwhile, how long until Facebook itself moves into the space?