Just want to note, that I've managed to get the USB Receiver up and running on an armv6 based RaspberryPi.
Very quick guide:
1. Enable DVB-USB and I2C Support on the Pi kernel (Howto: http://elinux.org/RPi_Kernel_Compilation
2. Compile the media_build drivers against the kernel sources from step 1.
3. Install kernel, drivers and firmware on the Pi and enjoy (more or less).
(4. Install vdr and the streamdev plugin to stream the signal to your local network)
There is a dmesg error message "i2c message failed" right after plugging in the USB receiver, but scanning and watching works. Sound is a bit laggy though. The CPU usage is around 40% (with 1 client connected to the vdr streaming server). So doing anything else on the Pi results in a very very laggy stream.