I fully appreciate the problem with not interoperable application and the large benefits of a fully URIed web; however, making progress in usability requires a flexibility that this scheme doesn’t match, hence the success not just of mobile apps, but Ajax before them -- success that occasionally went back to its origin and reassigned URI throughout (thank you GMail).
However, one thing is not true in what he says:
> Apps have a rich-get-richer dynamic
Yes, indeed, but so do websites; portalisation, or more simply the shear number of sites people visit spontaneously is not less than the number of apps they use regularly: three to five versus a dozen. There is a problem at the lower end of that spectrum: while the sites big enough overall to make an be maintained it are actually more common than apps that can do the same, users tend to spend an almost exclusive share their time in said ten-to-fifteen apps, and that challenges discoverability, i.e. the renewal of that class. That’s where the issue is, not in how many apps cover 80% of usage, or how many first letters people type before their browser auto-complete the rest.
(On that, I wonder how much the lack of success of Readability has to do with starting with the same letter as Reddit)