  In this note, we consider the observational constraints on some cosmological
models by using the 307 Union type Ia supernovae (SNIa), the 32 calibrated
Gamma-Ray Bursts (GRBs) at $z>1.4$, the updated shift parameter $R$ from WMAP
5-year data (WMAP5), and the distance parameter $A$ of the measurement of the
baryon acoustic oscillation (BAO) peak in the distribution of SDSS luminous red
galaxies with the updated scalar spectral index $n_s$ from WMAP5. The tighter
constraints obtained here update the ones obtained previously in the
literature.
