Please release Trisquel 7.1 and start 8 development
An updated ISO with newer packages, kernel, and xorg is long overdue. Make it happen.
Oh and with Ubuntu 16.04 releasing this April, please consider brainstorming some ideas now so we don't have to wait 4 months for Trisquel 8 to be released. MATE has been seeing a LOT of great improvements lately and by the time 16.04 is released, it will be in an excellent state and a prime candidate to be the default desktop environment.
A few things to ponder on any DE change:
Is it accessible? Can Orca function flawlessly in it?
Is it optimized for hardware without 3D acceleration?
Is it easy(ier) to maintain?
> Is it accessible? Can Orca function flawlessly in it?
Yes. Orca should work fine- or at least as well as in GNOME 2, which served
Trisquel well for a long time.
> Is it optimized for hardware without 3D acceleration?
It does not require 3D acceleration.
> Is it easy(ier) to maintain?
Yes. It is simply GNOME 2 with updates, as opposed to a Trisquel spinoff of
GNOME 3's 3D-less mode.
Also remember that Ubuntu MATE is an official version since Ubuntu 15.04 meaning that MATE packages in Trisquel 8 will be stable and receive security updates for 5 years (2016 to 2021).
MATE is a very active project and you can actually get the most recent backported versions for Trisquel 7 if you use the repositories for Linux Mint 17, which is based off of Ubuntu 14.04.
Be careful with that. As I've mentioned before, the Mint project doesn't make any effort to segregate libre from proprietary software in its repositories. For example, a quick search tells me that a package called "virtualbox-nonfree" is in the "main" repository for Mint 17 -- the same repository where Cinnamon is found. I'm going to go off on a limb here and say that this package probably contains some proprietary software.
Assuming Trisquel 8 is to be based on Ubuntu 16.04, does it make sense to start 8 development before there is even an Ubuntu Alpha out? If it's to be based on Debian or Parabola, then it could start, I guess.
I guess you are right in development being a little premature at this point. According to http://www.omgubuntu.co.uk/2015/10/ubuntu-16-04-release-schedule-release-schedule-date-xenial-xerus the first Alpha for Ubuntu MATE should be out in late December and would be a good time to start evaluating MATE as an option. It would be nice if the Trisquel themes are worked on to be more MATE friendly or at least modernized a bit.