I don't quite get that. This is standard (Kubuntu, etc.) maintenance.
Your right of course... but LinuxMCE-0710 is a complex beast and can easily get broken by standard Kubuntu system updates carried out via the system update daemon...
I get that. I really do. [Been there, done that.] kernel updates being rather different beasties than adding kdebase.
Back to the original question: Is there a problem with this sources.list entry?
broken or down?
i.e. Do I wait for the site to come back up, or just comment out those entries in sources.list.
The latter begging the question as to why it's present (post-install)?