Good question. The original iPhone was web-only for a year and developers clamored for access to native development. There is a long way to go until browsers pl

Good question. The original iPhone was web-only for a year and developers clamored for access to native development. There is a long way to go until browsers plus the web development stack can provide the same experience as native code, and until then "apps" are here to stay. Personally, I'm excited about it. People are making great applications for mobile devices that are not really possible in a web-only environment. Having to re-write them for different platform/device combinations is the price we pay for being able to build things that were not possible three years ago. What makes this so different from the mess of incompatible platforms twenty years ago is that today we have the web as a common denominator. As long as you can convert your data into html, you can share it with anyone regardless of what type of device they have. The whole "well, we are not both running Word on windows 95 on pc's with floppy drives, so we can't possibly collaborate" problem is essentially gone. Posterous has made a better mobile interface here than they could have on the web, but their web offering still exists. Anyone on any browser (or with an email account) can post to posterous, but if you have an iPhone, it is better.