Say what you will about Samsung (and we do - it's pretty much our job) but they don't mess around when it comes to timely source code availability. The company just posted the kernel source code for the Galaxy Note 10.1 2014 Edition, even though it hasn't been released yet. In fact, to our knowledge Samsung hasn't said where or when you can expect to see the shiny new tablet, or for how much. But by golly you can play with the kernel if you want.
The Note 10.1 2014 is essentially a blown-up version of the Galaxy Note 3, right down to the physical control buttons and faux leather back. It uses an Exynos octa-core processor and 3GB of RAM, along with an upgraded 8MP rear camera and the line's trademark S-Pen stylus. The screen is 2560x1600, which is really what the original Galaxy Note 10.1 should have used. Software is Android 4.3 with Samsung's newest version of TouchWiz, with plenty of added goodies to take advantage of the stylus functionality.
Samsung devices are usually pretty easy to unlock, and the Note 10.1 2014 will probably follow suit. That may not hold when the tablet comes to American carriers (because AT&T and Verizon like to lock up bootloaders like nobody's business) but the WiFi and unlocked models should be ripe for modding when they arrive. Whenever that might be.