Memento Mori, where? What?

Texture files in TARGA are out, DDS is the shit today. At first I thought this is a joke but now I see why. They choose TGA to display sum UI that has certain transparency which can't be made in DDS, cos they can compress it with the RLE id est - small size and yet no loss of quality. So far I know DDS can't be compressed without quality loss.
An example here at the login screen: