Amateurs maintain a blog on wordpress or blogger.com and a few friends and family might visit their blog, but we're talking under 1000 hits a year at the outside.
Semi pro might get paid by some outlets, and might have a blog that generates a decent amount of hits per month - but they've got a day job and they don't do it for a living.
Pros are doing this as a full time career.
Fair definitions?
The pros are absolutely "content professionals".
With that said, I have a bias and preference to the ASUS Transformer and it is for the reasons you outline. But... you've described the circular nature of my blogging pretty well, "I want devices that allow me to write about what devices are best suited to allowing me to write about how easy they make it for me to write."
It is a key driver for me in a mobile device. It isn't just writing, but a lot of it centers around the various things involved with that. I need powerful social media tools, it is nice if it can do a passable job at image and video manipulation and publication. A BIG thing that disappoints me with iOS and Android is the ability to easily cut a hyperlink URL and post it as a link in a document. Placing images and formating can also be a hassle in mobile OS platforms. Sophisticated document creation is one of the tasks where I'll write the document mobile and then modify it and polish it on a desktop later - which *is* a pain.
And I think that the old parable of the cook and their tools assumes that a great chef can make a great meal as long as they have a fire, a pan, and ingredients. That is probably true. I imagine a great blogger could write a masterpiece on their phone. But they probably *prefer* professional grade tools, just like a chef.
But there is bound to be disagreement among different cooks over which tools are the best for their trade.
