I finally finished a first patch to port dvbsrc and ts-tools (which are needed to convert the mpeg transport stream into something gstreamer can play) to 0.10. You can see the results at #344987.
Unfortunately the live playback of video does not work because of clocking issues that are far behind my gstreamer knowledge. Anyway, it's quite easy to record the mpeg stream and this really works good. DVB-S, DVB-C and DVB-T are supported though I only tested DVB-T
And want to thanks the people on #gstreamer and #linuxtv here for there patience and for answering all my questions!