Jeff, it's actually a bit more commonly used than the anecdotal evidence would lead you to suggest, it's just poorly named. To be fair, it also has a ton of different names it goes by, which makes it more confusing. "Banker's Rounding", "Unbiased Rounding", "Statistician's Rounding", "Convergent Rounding", "Round To Even", "Round Half Even", "Round to Nearest", etc. On the other hand, it's also the rounding method used by millions of .NET apps, whether the users know it or not, since that is how Math.Round worked until 2005 (it still works that way, but now you can use traditional rounding if you'd prefer). It's the default rounding method per IEEE 754 (this is probably the biggest reason), .NET, several of the ASTM committees, Delphi, and many others. It's available in almost every programming language, Mathematica, Matlab, Excel, and countless other apps. In fact, SQL Server is one of the only places where I've needed it, yet it didn't exist natively. On the other hand, it wouldn't surprise me if Katmai supported it.

I've probably used it on only about 10% of the projects I've consulted on, and even then, I don't think all of them needed it (two of them were just "I heard this is good, so use it" type situations), but for those who do, it would be nice to have a working function. Basically, it's a tool. It could be indispensible to one person, and never picked up by another. I just think it would be nice for those who need it to have a good quality tool.

So, to answer your question, it's not universally used, but it's far more common than you'd think, so yes, I do think it's a wise component to have around.