In Win 7 Pro 64bit, Task Manager shows inputPersonalization.exe taking almost constant 50% CPU usage. My Dell XPS 1530M laptop is now running hot. This all seemed to start after switching from one Wacom Bamboo tablet driver to another, then back to the original. The driver is the current correct one for the tablet.
Also, handwriting disappeared after this, and only System Restore got it back.
inputPersonalization.exe comes back if ended.
Uninstalled/Re-installed the tablet driver a couple of times to see if it solved anything. It didn't.