hehe... well how to install boot splash etc? does kubuntu have a branding package? altering it all?
If you mean the grub splash, a quick answer is no. You might find some info on grub splashing in Kubuntu that suits you here:
This should work in Mint KDE as well
Apart from that there is a gutsy kdm theme in the kdm theme bit of kcontrol and a kubuntu gutsy backround available under /usr/share/wallpapers/ in the beta 4.0 KDE Darnya Mint.
I hope this helps