(2010-11-08) 37signals Html5 Framework Coffee Script Eco

Thirty7 Signals is working on a new WebApp FrameWork where code will be comprised of local JavaScript, with the network just being used for data. The apps will work offline, when live data transfer isn’t required... It’s built in Coffee Script and Eco, a new templating language created by 37signals. Driven heavily by HTML-v5. They're saying it's focused on Mobile apps, but why limit it to that? Just to avoid MsIE issues?