Yes. Unfortunately, the balance seems heavily weighted toward the slow end of the curve, so that in practice it comes out slower than MRI.

It's not just for things like Rails apps that Ruby is typically used for, either. I frequently process data, such as large log files, and now and then I try out the different Ruby to see if things have gotten better. So far, 1.9 and JRuby are the winners.

(LuaJIT is typically 2-5 times faster than both, so these days I tend to write my scripts in Lua.)