There has been some debate on this topic recently, but hear me out:
1. In April 2013, all versions of Trisquel prior to 6 will lose their support. No more package updates or security fixes will be made available from Ubuntu for Trisquel to use. Trisquel 4 (based on Ubuntu 10.04) loses support for the desktop but the server packages will get updates for 2 more years. Every other release is unsupported.
2. In April 2013, Ubuntu 13.04 will be released and it is rumored to be the last non-LTS release for Ubuntu as they move to a rolling release model but continue to release LTS versions every 2 years.
3. If Ubuntu moves to a rolling release model, Trisquel does not have the resources to check packages daily (to blacklist and deblog) to make sure they are freedom friendly. There is already a struggle to get a release out the door and I doubt daily changes to the OS would helpful.
4. Trisquel 6 MAYBE gets released around the time of Ubuntu 13.04, meaning that it is two codebases behind. In the traditional numbering scheme, this would be Trisquel 7. Delays to 6 have seriously hurt the progress of Trisquel.
5. Is there a point in spending the resources to release Trisquel 6.5, based on 12.10, at this point? The code is 6 months old and is not good PR for Trisquel.
6. Updating from version to version has now become a pain. Ubuntu 12.04 cannot be easily upgraded to Ubuntu 13.04 without first updating to 12.10 and then 13.04. That would mean a Trisquel 6.5 has to be released in order for people to upgrade safely down the road if they want.
7. LTS releases are made to be updated from one version to the next and are heavily tested by Canonical and the community. This includes the desktop and the server.
8. Being LTS only means less emphasis on full releases and more on backporting newer packages from newer Ubuntu releases in a dedicated Trisquel repository for it. Packages from PPAs can be imported or custom tailored from source code for Trisquel.
So in a nutshell, with the recent changes to the release structure of Ubuntu and this project seeing heavy delays, the only way for Trisquel to survive at this point is being LTS only.
