Given that I missed some episodes, I gave it an A. For a first season, it did rather well -- the writers and the cast found their feet in good time, and the mere fact that I would try to hold on till one in the morning just to catch the replay will tell you how much the series engaged my attention!
That said, I must admit to a particular bias in favor of Gary Sinise, whose performance I adored in "Apollo 13". The bias grew stronger when CSI:NY was introduced in the crossover with CSI:Miami, but even as early as that, I noticed the way the cast had jelled as a team. Really cool.
So, with good plotlines, and more eye candy than should be legal on television ::grin:: what's not to love about the season?
^__^