We have a shortage of good developer talent, period. Whether it's only because we're in a startup bubble is anyone's guess. But in troubling fashion, some CTO-level people (such as the author of the linked blog post) claim that their difficulty in finding qualified Rails talent is driving them back to other less-desirable technologies such as PHP and .NET.
Do we think that people switching their projects away from Rails is a troubling trend? Will that trend cause the decline of Rails overall?