Jerky keyboard and mouse

[Stephen Montgomery-Smith]

I recently upgraded from stable-6 of Nov 4 to stable-6 of today on my 
Dell Latitude D800 Laptop, and suddenly the response of the touchpad 
mouse and keyboard was bery bad.  In particular, when I type about 1 in 
10 key presses simply do not register.  I ended up going back to the Nov 
4 stable-6, which fixed the problem.

Any ideas?  I am happy to provide any details you may need.

Stephen