Jade has a cleaner, more readable syntax and comes with filters and helpers: https://github.com/visionmedia/jade#a7
If you’re going to migrate HTML files to jade, this converter might come handy:
http://html2jade.aaron-powell.com/
…but you can also use HTML.
app.set('view engine', 'html');
http://expressjs.com/guide.html#view-rendering
I’m using EJS ( http://code.google.com/p/embeddedjavascript/) as the rendering engine in my express app, but keep a .html suffix on the template files like this:
app.set('view engine', 'html');
app.register('.html', require('ejs'));
(requires ejs be installed, which you can easily do via npm install ejs)