Just to add, while I am as upset as the OP is, I completely get why Apple isn't including transit directions and is relying on third-party apps. From their standpoint, it makes complete sense. But for those of us who would heavily use that feature, we're screwed.
Again, those saying it's only a beta and that something will later be included, no. A new feature like this is not going to be added, plus Apple has already stated their solution for this. And secondly, while using the web app would work, it won't be as effective. You lose so much functionality, although it would work in a pinch. And while using a possible Google Maps standalone app would provide almost the same functionality (aside from the bonuses that come with using the native map app on the OS), we shouldn't have to resort to that.
Again, there is a reason to be mad. But I'm going to take a step back here and say that we can't really blame Apple. They wanted to kickstart their new maps application, and it was going to come at a cost. Of course version 1.0 of their maps isn't going to be as robust as Google Maps.
And it would take a lot of effort for the transit information that comes with Google Maps to be included in Apple Maps. So the route Apple is taking, it's pretty smart.
I'm still upset, but looking at it objectively now, I don't think we can simply cry about it. Many of the points in the OP are spot-on, but you have to look at why Apple is doing it this year.
However, being the car-free person I am, this would be a feature I would use heavily. And I'm moving to a new city in the next few months, too. I'm also in the market for a smartphone, and I can't say with certainty that I'll be using an iPhone.
Our choices are basically to stay on iOS 5, or go to another platform. Even Windows Phone 8, announced today, provides an awesome solution. There is Android, too. But we're all here because we prefer iOS and the iPhone.
I also don't think this is some rare feature that most people don't use. We certainly aren't power map users just because we use transit directions.