The title of the post pretty much says it: "The Web Browser Address Bar is the New Command Line." By the way, I love the command line. It's fast and succinct. The only problem I can think of is that the command line relies on a good memory. If I don't use commands after a while, I forget them. When you add the shell to the command line, you get Unix magic!
The post mentions the site yubnub which really is the embodiment of the address bar as command line. I've tried yubnub but for some reason, I've never really felt a need for it.