Yet another opinion in Mono case
There were many Mono debates on Tuxmachines for last few weeks. Of course I have my own opinion on this topic. I will not blame Mono right now, just my thoughts about distributing it with Linuxes.
As far as I know, all those debates started when Debian guys thought about including Mono into default installation. But what it default installation? Isn't it related to target users? It's obvious that when you installing Ubuntu - you target home desktops, SLED or Mandrake - office, SLES or Slackware - servers. Depending on that choice "defaults" are very subjective. But is there any distribution problem? I don't see it. Being SUSE user I have my distribution on DVD media, lots of stuff could be fitted there, why not include Mono? If you're single CD distribution - you should think twice and count all Mono-based software you'd like to install. If it's just single application - it will be funny to install mono because of it.
Next, most of Mono apps are made for GNOME. I see no reasons to install it with KDE-based distribution, or console installations.
Thinking about users
In perfect world user should never bother with technology used in his favourite apps. Application should just do it's job, not promote or blame something. To mono or not to mono should depend on those user apps, but should not be some politics or religion choice. As for me I hate beagle, banshee and f-spot. Mono should not be installed for me. And vice-versa. If user will notice any Mono application he will run - it will look like there is some problem with Mono, don't you think so?
While it's completely OK to depend some desktop apps on Mono or other interpreted stuff - it's totally wrong to use it for system parts. Every next level of abstraction and interpretation adds additional level of possible problems, removes some part of integration and requires more resources to work. Can you imagine our world if HAL will be written in ruby or python or something like that? System must not be related on interpretator vendor or on subjective solutions. You may already see some bad examples like ZEN in SUSE 10.0, pulseaudio in current distributions, gcj instead of Sun JRE in fedoras and many more.
From my perspective
It's strange to see, but all mono-based apps I know makes me sick. Beagle that starts and scans event without any GUI installed. ZEN that made me think about switching away from SUSE. Banshee with it's crippled playlists. F-spot with it's lack of features. MonoDevelop with it's lame possibilities totally unexpected in any IDE. I think that the day I will not be able to set "taboo" on Mono in my SUSE installation will be the last day of me as SUSE user.