Disclaimer: I love my iPad far more than any laptop I've ever owned. I would choose an iPad over a laptop if given the choice. That's not what I'm trying to debate.
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So last night my GF was trying to watch a video from her online class. The video controls could not be accessed. Half the screen was shown with no way to view the entire video. She had to get on my Windows desktop to view the content.
These instances would prevent me from using an iPad as a laptop replacement. While the iPad is great at performing specific tasks, it's not a daily driver for students or people in the workforce.
Luckily, there's this thing called time. As time goes on, more and more things are designed for mobile. We're not at the point where you can fully replace a desktop based operating system, with a mobile one.
This will slowly change. There won't be a specific date for this change. A new iPad released by Apple won't fix the major issues plagued by iPads, because the issues revolve around compatibility and the content provider's willingness to make compatible content.
The real question is: is it good enough? Are you willing to ditch your 3 pound gorilla for the future of computing, even if the future hasn't fully arrived yet.
You think nobody has ever struggled to play a video back on a Windows computer? Do you know how many support calls I've fielded on this issue from family/friends/coworkers??