I too was once a Slackware user, and one thing I hated about it was
installing dependencies (I bet you know how fun that is). Trisquel uses dpkg
which automatically installs all dependencies and that's one of the main
reasons I love it. I'm sure switching will not be hard.
It is not very different from Ubuntu besides the repos. One big difference is
the WM, which doesn't use Unity. Also there isn't the big Amazon botnet/spy
tracking all your searches. Overall I would also say it is faster than
Ubuntu, and definitely uses less RAM on idle.
As for why the FSF is so proud of it, it is probably because it is the most
up to date. Compared to the old '98 interface of gNewSense (also known as
gNuisance), it is far superior. That is my guess as to why it is FSF's prized
distro of choice.
