It seems that this is caused by the splash+vt.handoff boot options. Apparently they are on by default, and the server cd uses a preseed to shut it off. The mini iso it seems does not do this. I discussed it in #ubuntu-devel, and there seemed to be consensus that either the option should default to off, and if you install one of the -desktop packages, it switch it on, or more likely, the vt.handoff machinery just needs ripped out and we run X.org on tty1 to avoid screen flicker like other distributions do.
It seems that this is caused by the splash+vt.handoff boot options. Apparently they are on by default, and the server cd uses a preseed to shut it off. The mini iso it seems does not do this. I discussed it in #ubuntu-devel, and there seemed to be consensus that either the option should default to off, and if you install one of the -desktop packages, it switch it on, or more likely, the vt.handoff machinery just needs ripped out and we run X.org on tty1 to avoid screen flicker like other distributions do.