This is an interesting presentation. I tend to find Ola to be a pretty
credible person because he has written Ioke for the JVM and CLR but he
makes lots of references to problems with MRI (both 1.8 and 1.9) and
how JRuby is better. I did not get this feeling when I attended the
presentation at Ruby Conf.
http://www.infoq.com/presentations/bini-power-on-jvm