I really agree with this, but think that we'll see even more of a split than just math/application. I got my PhD in Information Systems and Technology, which fused a social science approach with a topic of information systems being used in different domains. I found it really useful, and think that a business-oriented/programming-oriented/math-oriented division will probably split up the field.
Sounds pretty similar to Apple's earlier attitude about 3rd party developers being parasites on 'their' platform. While (of course) they do own it, the 3rd Party developers are partners that add value, not parasites.
Re: part-time. I was able to finish part-time, but did a ton of work full-time for the first couple of years. My research suffered, but because my job linked with the research, it worked out well.
One thing that's not well known is how much you'll be working while in school on grant-funded projects. You'll be working no matter what, it's just a matter of getting a good one to work on.
Re: age. This is a big deal. Younger (<30) have a large advantage, particularly with respect to the amount of free time you have available. Don't start a family during school. It's certainly possible, but slows you down, which is the major killer of graduating. If you're >50, your odds of a full-time teaching appointment are not good.
I just finished up a PhD in Information Systems & Technology, which is related to CS, but much more user-land/application-land oriented. Be careful which type of program you apply to, if you go CS, it takes a lot of math. Look to see if the degree department is part of a business school.
Your real focus is the dissertation; the rest of the courses essentially act as a MA/MS. Make sure your dissertation is marketable (biological stuff is probably the best bet to be hot in 5 years, security and games are hot now, but I'm not sure how much longer).
However, I'd really recommend against a PhD unless it (a) directly helps you in in a major way in your existing career, or (b) you want to become an academic. The latter is a tough field to make it in; go to a high-level university or don't bother. You'd better like submitting grants as well, and relocating is pretty much a requirement. I've enjoyed it, but it's incredibly stressful.
He's obviously made significant contributions, but I find his distain for industry off-putting. I wish we could separate computer science into theoretical v. applied research to clear up differences in the way the topic is approached.
What surprises me is not as much Apple's move (though it is truly ridiculous), as some apologists' responses. Talking about how "Adobe's just as bad," or that "it'll reduce crappy software in the store," or that "Apple's within their rights" is really missing the point.
The point is that this is totally unnecessary from a technological perspective. It's totally a business move to destroy competitors and pursue a bizarre vendetta against Adobe.
I teach in a business school, and am very 'pro competitive edge,' but this is just so short-sighted. Apple's competitive moves seem oriented to reducing anyone who could be a competitor to rubble out of some misguided belief that the iPhone paradigm is theirs, and that they should be able to dictate who makes money off of it.
Ultimately, any business adopting this approach dies. It make take 4-8 years for a competitor's product to reach equivalency, but it'll happen. Tech moves so fast that it'll be tough to keep a closed environment (even a good one) on top.
Furthermore, (and really to the point) I don't want to do business with any firm that thinks they can dictate if or how much profit I can make, or how I can approach my particular niche of interest. Apple keeps on reducing the way you can build apps; how do I know that my next app isn't going to compete with mobile Pages & get pulled? They're creating a totally closed and controlled platform, and you better hope that you don't run across any of their plans. It's a terrible business environment, and totally destructive.