True, but at the same time, it's not been *weeks*, it's been 11 working days since iOS 6 came out. I'm pretty sure the App Store Review team have had thousands of app submitted for updates for iOS 6, iPhone 5 and so on. It might be a failure on Apple's part to cope with the amount of published apps, but it's not really their problem to make companies use it.
They demoed it and presented their vision twice on stage. Whoever did not see the potential in that (company-wise) is probably really stupid. It might take a bit of time to get it sorted.
And also, the reason there's no iPhone 5 support is because of the way they treat newly published apps. If one adds a splash screen image for iPhone 5, the minimum OS required has to be iOS 6. Hence the companies/developers that don't have iPhone 5 support yet are trying not to lock down their iOS 5 customers.