If anybody’s interested, I’ve set up a repository for tracking changes in Inform 7 extensions at the following location:
I’ve got about one year’s worth of data there, and I usually check for changes every 15 days or so.
Feel free to fork if you wish. 
well thank you!
Excellent!
What would be great is if the whole extensions site was managed by git.
Thanks!
Or Mercurial, or any DVCS, really. 
I’m just not sure how much load on the I7 servers it would be compared to using iXu, which is what I’ve been using to get updates.
The above url: github.com/acl79/i7-exts
gives a 404 when clicked on.
It’s been moved to github.com/i7/extensions , as noted in “github/i7” thread.