The current Rigol driver in sigrok supports the VS5000, DS1000, DS2000 and (Agilent-branded) DSO1000 series. It has various workarounds for quirks in some models and early firmware versions, but in general the later models seem to be more straightforward to support. Have a look at the code:
http://sigrok.org/gitweb/?p=libsigrok.git;a=tree;f=src/hardware/rigol-ds;hb=HEADWith a little bit of luck, adding the models in the DS1000Z series to the list with similar options to the DS2000 series should get most of it working. I expect thorough testing of all the options to be the biggest part of the job.
Can one of you guys create a page on the wiki about the series, preferrably with some pictures? Something like this:
http://sigrok.org/wiki/Rigol_DS2000_seriesPM me here for a wiki account, or join us on IRC at freenode #sigrok and ask there.