I'm a *little* concerned about the performance implications of this, depending on where deprecation warnings end up showing up. According to [this page](http://jsperf.com/getting-error-stack), Chrome appears to be really slow at generating stacks (where "really slow" is 7,500 ops/sec on my machine... Aurora is 100x faster and Safari is a suspicious 10x faster than that!). The way this function worked previously, if the message is a repeat, there's no stack trace generated.

As long as this isn't called *a lot*, it shouldn't be a problem. But, I can imagine wanting to use this in instances where it is called a lot.