It's not the only bit that's wrong, but it's worth pointing out that community run servers would not have saved Halo 2 from shutdown, because servers were not the issue.
While Halo 2 has a client-server networking model, it doesn't take over until the match is set up, and one of the client Xboxes is chosen as the server. The job of setting things up is handled by Xbox Live's servers (so you can login to your XBL profile on your Xbox) and Bungie's matchmaking servers (that handles playlists and player rankings).
Halo 2 was shut off because changes to Microsoft's XBL service were made that were not being backported to the original Xbox. Online support for all original consoles and original games in emulation was dropped on that day-- regardless of the number of Xbox clients out there that were still potential "community run" servers.
To keep Halo 2 running you wouldn't have needed instances of Halo 2 running, since those were already irrelevant. You'd have needed an emulator of Microsoft's original Xbox Live service running.
That is all aside from the point that community run servers are not actually better, unless you run one yourself. There's no reason to believe the average community moderator would be much better than the average Halo player, considering that you wouldn't run such a server unless you're a player of the game.
The whole point of XBL was to address things that were missing and broken in the dedicated server model, and taking a step backwards makes no sense.
Matching by skill? Can't happen with dedicated servers, since they don't communicate to each other.
Reliable, persistent statistics about all games you've played ever, at a central location so you can review and share? Can't happen with dedicated servers, unless you figure out how to crack open your console and do analysis on your own logfiles. The server logfiles are spread around with the servers. They don't talk to each other, and you have no idea when one will go offline, become unavailable, or be retired. Not to mention that now the developers can't do features like playlists, because the problem of managing optional map packs has now been multiplied by the size of your community moderated server population. Do they have to pay for maps? Do they get them all for free?
All Xbox Live games use Xbox consoles as servers. What are these community servers going to run on? How can individual console owners/XBL subscribers be given the kind of administrative access over multiplayer games running on their console without compromising safety and fairness? Shouldn't server admins be prohibited from playing on their own server, for fear of unfair advantage? If you restrict an admin's access, in what way is it actually a dedicated server?
I'm not really sure what Shamus is really asking Microsoft to do-- and I'm not sure he does, either, beyond a vague sort of nostalgia for the halcyon days of PC gaming where you spent more time looking for servers than actually playing.
What I am sure of, is that there is no way which matters where that model is better than what XBL does.
As for TF2-- Microsoft won't let a rival platform owner (Steam is a platform) distribute content for free through XBL. This is a surprise?
Many have noticed that in order to keep pace, if a publisher gives away something on PS3, they make it free on XBL as well. Of course, Valve has a nice excuse there-- they like PSN, but updating TF2 on PS3 is EA's job. So PC gamers are downloading multiple updates per day (wait, this is an advantage?) and console owners get nothing-- but somehow that's EA's fault and Microsoft's fault, not Valve's fault or Sony's fault, and of course there is no way this is actually just part of a power struggle between Microsoft and Valve over pricing and distribution. No way. Not a bit of it. Shame on you for thinking it.
