Here's the list of outlets and writers that got access to the iPad for an early review. You'll note that Boing Boing is on there, as is PC Magazine. Engadget and Gizmodo (along with TUAW, though we got one anyway) are not. Time is on there, Newsweek is not. Clearly, Apple's being careful about who's given access, and there's no one reason why an outlet might be on the list or not.
And it might be even more confusing than that -- Fake Steve Jobs (a.k.a. writer Dan Lyons) tells a story about how Apple sent word out that they were unhappy about Newsweek officially hiring him after the FSJ reveal. Apple isn't just controlling access -- they're doing their best to control the entire media perception of the company.
One thing that Beschizza doesn't mention (he goes on to gloat a little about Boing Boing's history with Apple) is that, in those first few days of iPad app reveals, it was pretty clear which developers had gotten an iPad early. Firemint, PopCap, MLB, EA -- there are hundreds of thousands of developers on the App Store, and Apple came to only a few to offer them a development iPad to play with early.
Unfortunately, again, we'll never know the criteria for selection there other than Apple's whims (and I presume the whole thing is wrapped so tightly in an NDA that we won't even know when and how the offers were made), so we don't have a full picture of what access was offered and how. But there's no question that Apple made specific choices about how and where to send the iPad -- some people and companies got in, lots didn't.