Hillary didn't run because the time wasn't right for her.
It's a bit early to be making that sort of statement. Again, I'd not want to have to bet it but, if I had to, I'd bet Hillary was running this year.
Here's the reasoning involved:
Basically, the Clintons have major kinds of legal problems which, long term, nothing but the power of the presidency can protect them from.
Moreover, it seems fairly obvious that the demmunists demanded and got an agreement that the Clintons and all members of their administration for that matter were above the law, as their price for ceding power in 2000.
The only question is, how long and with who is that deal good for? Clearly it's good as long as W. is in office. Nonetheless, a meteorite could fall on W. or, God forbid, some other mishap might befall him. Would Dick Cheney or some other designated successor honor the immunity deal for the Clintons?
Worse yet, suppose Howard Dean or John Kerry were to be elected president. Both of those guys have at least as much reason to hate the Clintons as any republican does, and they could turn the justice department loose on them and claim they were showing even-handedness doing it.
In other words, in Hillary's position, I'd rather wait until 08, but I wouldn't risk it if I thought I had any chance at all of winning in 04. Trying to wait till 08 simply puts too much power into the hands of fate.