In my opinion "Yes". Microsoft should stop working more on C# 3.1 or 4.0 currently.
The progress on DLR and IronRuby and IronPython is dead slow. The announcement of DLR was made at MIX 2007 in March 2007. The next MIX 2008 is round the corner starting from 5th March 2008. Even after one year the current stage of IronRuby is alpha stage only. No news on the IDE and no special section on forums to discuss DLR or Dynamic languages.