An interesting characterisation of the web's problems as five paradoxes by the new, provocativly titled blog 'Abandon the Web':

1. Everything is free, yet nothing is free. (Compensation paradox)
2. We don't know who you are, yet there is no privacy. (Identity paradox)
3. Write multiple times, yet it still doesn't run everywhere. (Compatibility paradox)
4. Code goes over the network, yet it's not mobile. (Boundary paradox)
5. The Web is not decentralized enough, yet it is not centralized enough. (Responsibility paradox)

Nothing really new, but it's still a succinct description of some of the key problems. Of course, despite these paradoxes, somehow you're still managing to read this post...