relevant, for mercurial:

hg has an extension for that http://mercurial.selenic.com/wiki/ChurnExtension

results are easy to parse to generate some other view

  zalew:~/webprojects/x$ hg churn -f '%u-%a' -s
  1-Mon   1690 **
  2-Tue   4756 ******
  3-Wed   3007 ****
  5-Fri  70758 ****************************************************************************************
  (dj125)2011-10-25 17:38:36
  zalew:~/webprojects/x$ hg churn -f '%u-%a' -s -c
  1-Mon     12 *****************************************
  2-Tue     26 ****************************************************************************************
  3-Wed      4 **************
  5-Fri      9 ******************************
  (dj125)2011-10-25 17:38:58
  zalew:~/webprojects/x$ hg churn -f '%H' -s -c
  02      1 **********
  03      4 ****************************************
  04      6 *************************************************************
  05      3 ******************************
  06      8 *********************************************************************************
  07      3 ******************************
  11      1 **********
  12      2 ********************
  13      3 ******************************
  14      5 ***************************************************
  15      3 ******************************
  16      9 *******************************************************************************************
  17      3 ******************************