There's a point that seems to be being missed here, and that is that while the N900 doesn't by default run completely free software, the hardware is broadly accessible - Open, to that point that if you wish, you can completely wipe the existing operating system and start out with something 100% opensource like Mer.

To me, this is the revolutionary step that Nokia, and no other mainsteam manufacturer (to my knowledge) has taken. If you want to port VLC over, go for it! If you want to port Pidgin, great! Want to figure out a way to tether your laptop via bluetooth or wifi, Nokia won't stop you.

In contrast, Apple will say "I'm sorry, but that app replicates existing functionality, regardless of whether your app does that better or not." Even Google/HTC has worked to prevent tethering apps from being allowed on North American versions of the G1. Certainly none of these manufactures will provide an easy path to flashing your phone with an entirely different operating system, and such behavior may actually be a breach of contract.

Overall, I care more about Open Hardware than I do about Open Software, because you must first have access to the foundational equipment before you can worry about programs to make it do new and exciting things. I get mildly excited that Nokia has announced plans to make Symbian 100% open source, but since I'm not going to be able to recompile my own distro of it and successfully load it onto my N97 any time soon, and since I need a developer certificate to even load my own software I'm not rushing out the door. However; being able to use and program all the parts of my N900, just like I would a computer (even one that comes with Windows preinstalled) does make me excited, and does greatly serve the open source community, which till now has had little to really look forward to in mainstream devices.