Two trends that are helping the demise of PCs are cloud computing and Software-as-a-Service (SaaS). Both trends alleviate the need for better hardware in the devices used by you and me, hence the popularity of smart phones and tablets as computing devices and not just as phones or electronic books. SaaS programs are run on a cloud server somewhere, and all you need is a device, like a tablet, to interface with the remote server running your CAD or spreadsheet program. You don't need to install these programs on your device.
The end result is that you won't need a PC. Tablets of all sizes will be cheap and available. SaaS has a long way to go, though. I'm not sure how many architectural CAD programs are yet sold in this manner, where you essentially rent a license for a prescribed period and run it remotely on a cloud server. I suspect we will be using PCs for a few more years before SaaS becomes prevalent, affordable, and reliable (such as what happens if you are trying to work somewhere without good internet access).
When it comes to technology, the standard disclaimer applies: that's all subject to change if something new blows that stuff out of the water.
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Kris Weeks Assoc. AIA
Intern Architect
Caolo & Bieniek Associates, Inc.
Chicopee, MA
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