Little Video below of Nokia showing some of the "Openness" that MeeGo / Maemo operating systems boast. The N9 has a developer mode that can be easily switched on in the setting that will allow complete access to a Root and Debugging. Take a look:
One of the things that is not mentioned is that the open unrestricted handsets will be the ones purchased directly from Nokia. Most likely if the handset is purchased from Mobile Operators this functionality will be disabled. Don't worry, as your now dealing with the MeeGo community there will be a simple work around (most likely), something like run a little script and your in, like you can do on the Nokia N900.