I got an email from Matt Mullenweg with a pointer to a JSONification of his RSS feed.

He says: "Now included in the beta 1 of WP 3.8 we just released."

I wrote a little JavaScript app to read the file, and it works. Look ma, no server!

View Source to see how it works.

Now you can write a nice WordPress blog browser without a proxy server.

Next step is obviously an equivalent writing interface.