The two best sites i've found for wide-ranging and even-handed coverage are Just One Minute and The Daily Howler. They do more than just chew over the day's headlines, they know the difference between fact and speculation, and they are willing to broach issues that complicate simple partisan positions.
Take JOM's follow-up on one of the early positions adopted by the Bush/Rove camp:
It may well be that insiders were well aware of her employment at the CIA. However, almost two years have passed and none of these insiders have come forward to say so. If Mr. May could amplify or clarify his anecdote, there is no time like the present.
Here's the Howler on why Wilson's credibility should matter to liberals:
Starting in July 2003, the mainstream understanding of this issue was largely framed by Wilson. Many of the things you assume to be true came to you from Wilson’s account. But, for all his manifest virtues, Wilson has frequently been a shaky witness; unfortunately, his misstatements have been bold and fairly common. From that, we would draw the following judgment—if you want to know what really happened, you probably shouldn’t simply assume that his frameworks are accurate. By the way, how do you know that Plame was still connected to valuable US security assets? You mainly “know” that because Wilson told you. As we have said, we get the impression that Fitzgerald agrees. But we are going to hold our judgment until we learn from a documented source.
There’s a million good things to be said about Wilson—but accuracy hasn’t been one of his strong suits. In the next few days, we’ll continue to sketch what we have in mind by all this—the frameworks which have come from Wilson, and the reason to be careful about assuming they’re true.