I disagree completely. I find my tablet a killer productivity tool, and only wish it had been available for use in filmmaking years ago. The only reason that I didn't build my production sound recording rig around a tablet computer was that the cost was so high; the only tablets powerful enough to run an operating system and record multi-channel audio were also built and priced for military or industrial use and severely limited by battery capacity. a 6-channel hard-disk based digital recorder cost close to $10,000 a few years ago. That same functionality (and much much more) will be available via tablet+USB audio interface within a year for $1000.

People said the exact same thing when the mouse and GUI came along - it was eye-candy, a substitute designed to distract the credulous from the fact that we had hit the limits of productivity and that it was all downhill from here on. They said the same thing about microcomputers and minicomputers as substitute for mainframe terminals.

In terms of desktop publishing you might be right, but I think we've seen amazing strides in the realms of audio and video production in the past ten years. It's now possible to buy cameras and audio recording gear for pennies on the dollar of what you used to pay for tools with similar capabilities. Meanwhile the software side of things has advanced just as rapidly... For example, I had to do some noise reduction on some audio recordings a couple of weeks ago and what used to take hours to do in early iterations of Protools now only takes a few clicks in Adobe's Audition (and probably in the latest version of protools too...). Photoshop, Illustrator, Flash... All of these tools have advanced considerably in the last few years, much less the last decade.

Tablets have any number of interesting productivity software being developed for them (innovative word processors spring immediately to mind), but developers are severely limited by the hardware capabilities of those platforms... Obviously we won't see a full fledged version of Photoshop or Final Cut written for a tablet for many years to come, but I think we might see that eventually.

I am optimistic that we will see those higher-end tools in tablet form sooner, rather than later. All it would really take is a step up in multi-touch precision. Steve Jobs has famously ripped on the stylus, but to have fine pen precision (like Wacom already offers) in additional to simple finger manipulation could end all doubt about a tablet's ability to replace a PC. It could switch from writing/drawing/manipulating with a gigantic crayon, to a fine mechanical pencil.

I imagine developers will produce interesting productivity software for these platforms, but I think the form factor inherently privileges consumption. There are the ergonomics, for example. Also limited screen size, and necessarily limited input. Maybe my overall point, though, is that with development going into optimizing consumption, less goes to figuring out more robust ways to interact with a more powerful platform. I feel like the desktop GUI has stagnated over the last couple of decades, and now there's less hope than ever that there's going to be any significant innovation in this vector.

It might be just an inherent lag between optimized mass consumption, and new innovative production. Scaling the Web out to the mass market happened first, next-generation innovations like Google showed up later. It is discouraging the direction is moving toward walled gardens. But there's a plus side to getting the platform out there to millions, making it more valuable to build innovations on. I can live with it as long as it's not one company owning the whole market, or a hundred small incompatible ones.

Machines optimized for creating stuff keep getting better, and aren't going away. I don't think it's necessarily bad if those machines drop to a smaller market share. It's usually a much smaller percent of people who create the apps and content that aren't crap anyway, and most of the consumer audience goes to them. Getting optimized video production machines out to the masses via cellphones is cool, but it's not really improving the average video on YouTube.

For creative ideas at the OS and interaction levels though... yeah, the platform owners need or want to own most of it. I think they're OK with jailbreaking the platform to the extent it creates a testing ground for new ideas, that they can then adopt.

I think it seems you have decided on this view and regardless of all the evidence of the contrary you are sticking with it..