I don't have a lot to add, but I'd like to present the April 2011 BsRized standings (without commentary). Team-level Base Runs were generated using the following formula in conjunction with data from Baseball Reference:

A = H + BB + HBP - HR - 0.5*IBB

B = [1.4×TB - 0.6×H - 3×HR + 0.1×(BB + HBP - IBB) + 0.9×(SB - CS - GIDP)]×1.1

C = AB - H + CS + GIDP

D = HR

BsR = A*B/(B+C) + D

The team-level Base Runs were used in the win% estimator PythagenPat to compile the standings.

NL East

NL Central

NL West

AL East

AL Central

AL West

Overall

AL teams light blue, NL teams white.

These have not been adjusted for the quality of the opposition.