for those keeping track, mist depends on (at least) 2 packages which there are open RFPs for.
1) meteor
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=842425( it also requires the version of nodejs that's currently in 'experimental' )
In addition, versions of mist have been (pre)released since 0.7 -- in particular 0.8.7 which only uses the version of nodejs that is available in sid.