Correct, Apple has been dropping the ball for quite some time now. The 12 PowerBook had a dedicated GPU, so its not out of the question. The problem is that they are being greedy and not giving those that want a smaller PRO laptop an option.
I think Apple got caught between a rock and a hard place, with regards to the whole Intel - Nvidia legal issues. Now that they are resolved, we can only hope that the 13" mbp's evolution will continue the way it should.
Also keep in mind that other similar sized laptops with Core processors and dedicated GPUs have cons about them, i.e. heat issues and short battery life. Apple has always gone for the best all around performance, not just max specs on paper that don't play well when assembled together - that's what PCs are for.