Summary

TT3 is more like Perl
...and Javascript
...and Python
...and Ruby
...and Lisp
...and SQL
...and BASIC
...and Algol68
...and HAML, Zen-HTML, Zen-CSS, etc.
...and whatever you want it to be

Thus Spake Andy:

TT3 is more like Perl so there are less surprises for Perl programmers. In places it's also more like Javascript, Python and Ruby. It strives for the same conceptual elegance as Lisp where the core language defines a few simple syntactical constructs that can then be combined in an infinite number of interesting ways. But without all the parenthesis! I much prefer languages that read more like spoken languages. Not wordy like Java, but more like SQL, BASIC and Algol68 in particular. Not content with mixing in elements from half a dozen different programming languages, TT3 also embraces declarative domain-specific languages like HAML. Writing your own commands is really easy. It's much, much simpler than trying to write your own template language, processor, or other framework from scratch. So if you have an idea for something that you think a template language should have, you can implement it and be using it in 5 minutes. And you get all the framework, debugging tools, caching, and other things that TT3 provides thrown in for free.