Deviation from the Cosmological Constant or Systematic Errors?
  Motivated by the fact that both SNe Ia and GRBs seem to prefer a dark energy
EOS greater than -1 at redshifts $z \gtrsim 0.5$, we perform a careful
investigation on this situation. We find that the deviation of dark energy from
the cosmological constant at redshifts $z \gtrsim 0.5$ is large enough that we
should pay close attention to it with future observational data. Such a
deviation may arise from some biasing systematic errors in the handling of SNe
Ia and/or GRBs or more interestingly from the nature of the dark energy itself.
