I think the main benefits of dynamic languages can be boiled down to
- Rapid development
- Glue
The short design-code-test cycle time makes dynamic languages ideal for prototyping, tools, and quick & dirty one-off scripts. IMHO, the latter two can make a huge impact on a programmer's productivity. It amazes me how many people trudge through things manually instead of whipping up a tool to do it for them. I think it's because they don't have something like Perl in their toolbox.
The ability to interface with just about anything (other programs or languages, databases, etc.) makes it easy to reuse existing work and automate tasks that would otherwise need to be done manually.
