Dreaming about a big 4.7-inch BlackBerry 10 smartphone? Don’t count it on it showing up anytime soon, as in a follow-up Q&A session to this morning’s BlackBerry 10 launch event, CEO Thorsten Heins confirmed that the screen configurations used on the new Z10 and Q10 models will be those the company sticks with for future BB10 handsets. That means a 4.2-inch widescreen 1280 ...