Five years later, the facts on the ground have finally changed. I no longer believe that this bargain is worth it for most new applications.

Javascript required? In other words, one cannot do this on cross-site iframes (due to cross-site scripting restrictions), is that right? As @clankill3r is suggesting, this demonstrates the need for a pure CSS solution to this problem

makes your app inaccessible to users if JavaScript fails or is disabled (which happens more often than you probably think).