I've read these threads for months now. I've also been taking stock of the current tech industry, and as a total neophyte to computers and so forth, I have a few (perhaps ignorant) opinions of my own. Here is what I see happening:
1. Downloadable content will become the de facto standard for those who want it to be. There isn't any reason why physical media, DVDs, BRDs, etc. cannot continue to be produced, they just will progressively wane in importance. Similar to how DVDs inched in on VHS; progressive rather than abrupt market transition meanwhile sucking every last penny from the outgoing standard while also profiting like crazy from the overpriced emerging standard.
2. Online software will become more prevalent as widespread, high-speed wireless access becomes ubiquitous.
3. Cloud storage of most photos, videos, music, etc (subscription access services to entire catalogs, labels, and so on) will take over. Home servers will fulfill other storage needs at various levels of complexity.
4. Desktops and conventional laptops will be replaced by tablet-esque devices in a variety of form factors, from iPod touch sized all the way to full-blown 12" or so slab sized. These will have solid state drives, ARM-based or otherwise low power CPUs, and will use something like CF cards or SD cards as swappable storage media. Everyone at home will have 50" or 60" or whatever sized LCDs, TVs, monitors, you name it. The little tablet thing you carry around is like the "brain", and the home server is kinda like the warehouse. You can access all your stuff on the go anywhere from your little
"brain" tablet. Meanwhile, when you go home, or to the office, to the dentist, or anywhere for that matter, you simply plug in the little "brain" tablet into a monitor-keyboard-mouse or whatever setup. Presto, all your junk at your fingertips ANYWHERE.
Bottom line: the iPod touch concept will metastasize into being powerful enough or capable enough to function as a standalone tablet thing that will simply be plugged into giant monitors, projectors, screens, etc. of all types anywhere you go. And, thanks to wireless and your server/cloud depot, you can access junk anywhere.
Sounds like the best solution to many, many problems. You can work in low-power options and renewable power sources for many of these and drastically cut energy usage. Big companies can downsize because work can be done anywhere, requiring less physical space for big companies to rent, own, buy, etc. More and more people will do their work at home, or in communal settings, rather than corporate metropolises.
I'm digressing...
I think Apple sees this progression, and realizes that the future of mobile computing and specifically small form-factor, full-powered devices is the next iPod-like market. Other competitors are already marching down that road (Sony's looks awesome!), it is only a matter of time before conventional desktop sales are roughly 1/3 of laptop sales, then 1/4, then 1/5, and so on down the line. Frankly, I don't see the need for desktops in about 80% of the workflows I encounter. I don't think they will ever die completely, but they certainly won't be the living room appliance they are today. Apple is waiting for the netbook market to begin to move toward the scheme I proposed above (just like the MP3 player market before the iPod) before they add their offering to the table.
No earlier than 2011 is my guess. Solid state drives need to drop to about 40% of current prices, market penetration of touch-driven interfaces needs to be widespread, and people need to above all feel an overwhelming compulsive NEED to have their digital life as on hand and accessible they same way they need their cell phone, wallet, car keys, etc. Convergence is happening (iPhone), but it takes time.
That's my 50,000,000 Turkish lira (2 cents).