Unless I'm mistaken, the only way to see the name of your current file is to run a Save command and see the name in the dialog. It would be really helpful to show the current filename in the header. Benefits include:

• Ensures I'm editing the file I think I'm editing

• Could show if the file is "dirty," e.g. by adding an asterisk

• Could me navigate the file path by right-clicking the name (at least that's what I'm used to on Mac)

• Could lay the groundwork for a tabbed interface for editing multiple files