According to https://github.com/blog/642-smart-http-support
http is correct, https is for private repos, or to have push access on your repository.
Just seems github is having issues with http right now, reverting to git solves this.
(I've tested and am syncing without error now)
Once I get my ics branch up I'll let you guys know. Do you mind if I merge in OpenSensation sources to it? Some makefiles would need to be changed in the device source tree but it wouldn't be that difficult. If you want push access to it the site is here:
Let me know and I'll see about adding in more members once the ics branch is up and running.