Correct. There's a button to check for updates, also, on the Summary tab. That's probably just a feel-good button, though, since it would be logical to check when you plug in your phone.
Damn.. The iPhone hackers really are fighting an up hill battle then. If they hack it to install their own apps, Apple will just release a patch to stop them.
I was kinda hoping updating would be more difficult so that the hackers could put pressure on Apple to release an open SDK.