Tonight Nintendo laid to rest one of the most criticized aspects of last years E3 show.
Nintendo originally said you may be only able to use one GamePad (Tablet) on a console at a time. 

Tonight Nintendo said that is indeed false and you can use two simultaneously on one Wii U console. 
That certainly is great news, the bad parts is that when using two GamePads together, gameplay is shunted down to 30fps in most titles.