Used the tablet all day yesterday without any problems. Put it to sleep last night, and woke up this morning to read a book for a bit after checking XDA. Touches started getting laggy and progressively worse as I navigated XDA. Then I went back to the home screen (very laggy), opened the book app (took 10 seconds), tried to open the book, and it barfed on the touch/highlight animation. The book never opened. Time elapsed from the point where I started noticing performance problems was about two minutes.
What was running overnight...
Connectivity: Wifi was constantly connected.
Apps: Gapps were polling regularly as configured by default.
Widgets: HD Widgets has 4 switch widgets on the main desktop as well as clock/weather. No other widgets running.
Including what I ran this morning there aren't a lot of variables. I was able to reboot by holding the power button down and everything was back to normal. Time to do some bug hunting. Perhaps there's a memory leak I can sniff out.