NaCl is disabled by default on the Cr48 development laptop. I would at least hope this means they start enabling NaCl by default in the ChromeOS source tree.
The article mentions a clear criterion for flipping the on-by-default switch:
"We’ll also be working on Dynamic Shared Objects (DSOs), a feature that will eventually allow us to provide Application Binary Interface (ABI) stability.
[...]
Until the ABI becomes stable, Native Client will remain off by default. "
