Are there any plans that anyone has heard of about the Thinkpad Tablet 2 getting any upgrades or changes?
Are you asking about a new Thinkpad Tablet model, or updates to the current TPT2? If you're asking about updates, I'm 99% sure that Windows 8.1 will be free to upgrade to, and I think you can download the 8.1 preview as well. Other than that, no clue.
About a new model, we haven't heard anything but I wouldn't be surprised if Lenovo comes out with a Thinkpad Tablet 3 around November-January. I would expect it to come with a stylus and digitizer like the current Thinkpad Tablets. We might see improved screen resolution but I think the real difference will be that it will use Intel's new Atom processor or just an improved processor in general (that HOPEFULLY retains the great battery life of the current Atom processor).
That's just what I would expect. However, since this is Lenovo we're talking, don't expect a pocket friendly price tag to go along with this device.
I'm just speculating here. But I do expect a whole new wave of Windows 8 tablets to come when Intel releases their new processors, around the end of this year. So the question you need to answer is, can you wait and will you be willing to pay the MSRP? Or do you need a tablet now and don't want to spend as much?
I personally do not want to wait and do not want to spend a lot on a tablet (not now, anyways). I don't need amazing performance so I'm getting a Thinkpad Tablet 2 next week. Since I'm only 16 and I don't have a real job, $450 is already a lot of money but I think it's reasonable for what I'm getting. In the next year or two when I do have a real job I'll get something better.
It really all depends on you and what you need. Good luck!