This is the dumbest thing I've seen since someone claimed that 37 Signals made an app with 171 lines of code. Of course you can make a short program if you make tons of assumptions and build them into your libraries. The fact is, no one will want the ugly form his Arc library is preset to generate and someone will want it to do something with JavaScript and someone else will complain that the JS doesn't work on Safari and it will all fall to pieces. You simply can't abstract the web that much and have anything remotely useful.
This is also a terrible idea because of the mindless focus on removing characters that it encourages. Look at this quote from the Catalyst one: "...work's underway to tersen up the syntax." Please don't! The syntax is totally unreadable already.