I don't currently have an opinion on this backport proposal, but in regard to this argument: if we do not do any 2.x releases after 2.7, then over time the number of packages that can afford to drop 2.6 support will grow, yet many will need to retain 2.7 support for much longer.
I don't think the argument applies to 2.7 as much as it applied to earlier releases: 2.7 will have a life time of 18 months perhaps (I think we still need to decide formally against 2.8, and also decide when to make the last 2.7 bug fix release). There is some likelihood that by the time people can agree to drop 2.6 support, 2.7 will be out of bug fix maintenance already (*). I'm fairly skeptical that people will be interested in adding new code to specifically clean up their 2.x codebase. Regards, Martin (*) just as it happened with any other release: people are now dropping support for 2.3, when this got out of security fixes a year ago. By that measure, people will drop 2.6 support in 2015. I think there are *really* good chances that many packages will drop 2.6 support along with dropping 2.x altogether.