In case you've misunderstood the Apple's marketing department:
1. They clearly see the iPad as a product that fills the void between smartphones and laptops;
2. iOS was first introduced without an SDK because webapps could just as easily do the job. That is why you can bookmark webpages as icons on the homescreen, however; webapps don't generate revenue and small startups can't afford gigantic server costs and so the appstore was a drop-in replacement to lower the barrier to entry;
3. Programming and post-PC are not realy compatible terms.
Anyone trying to use an iPad to program applications hasn't realy understood anything about the very purpouse of the iPad, whatsoever. Now there are people who researched the idea of visual programming, but thus far any attempt in R&Ding this dumb idea has "Microsoft Frontpage" written all over it.