Samsung beefing up the entire device, changing the dual-core 1.4GHz Exynos processor to quad-core and generously adding a holster for the S Pen. We wouldn't think that adding the holster would be too much of a bother, but upgrading the processor requires a lot of testing. Even so, let's not go so quickly to that place because this could just be the case of someone making a simple mistake.
Regardless, if you were hoping that your Samsung GALAXY Note 10.1 was just 3 to 5 weeks away, you're going to have to somehow suck it up and keep going. Besides, we should see a launch for the tablet some time!