Seeing as how this is apparently going to be a widespread issue, if you're having any driver issues after you update to Windows 8.1 (most notably video driver issues), then give this driver package a try.
http://global-download.acer.com/GDFiles/Driver/Others/Others_Acer_1.01_W8x86_A.zip?acerid=635164508727475738&Step1=TABLET&Step2=ICONIA%20W&Step3=W3-810&OS=ALL&LC=en&BC=ACER&SC=PA_6I work at an office supply retail chain specializing in staples, and our Iconia W3 demo started flickering animations after I updated it to 8.1 earlier this month. I thought nothing of it and guessed it was a issue with this particular unit. But apparently not now that its out for the public. Cheers!