Interesting discussion on Ruby on Rails and Scalability

... can be found here:
The Joel on Software Discussion Group - What's all the fuss about Ruby On Rails?

This is a good point when discussing about scalability:

"Besides, arguments about scalability are a non-issue.

Ruby On Rails pushes most of the hard work onto the most proven of all scalable workhorses: the relational database.

Proponents of the Java stack may crow about the scalability of their frameworks, but on the frontline it is choking in complexity.

Long term, complexity is as important as performance.

True, Rails is yet to prove itself in terms of scalability, but Java still has some way to go.

Rails can do the simplicity, but can it manage the performance?

Java can do the performance, but can it manage the simplicity?

Remember that Java was once the slow, unproven contender itself. It won out against C because of reduced complexity, not because of increased performance."