The fact that internet connectivity on a desktop vs. on your mobile device is different by an order of magnitude. When you get ubiquitous and fast internet on the mobile device (not some bizarre spotty coverage), then things will change. Maybe Europe is ahead in regards to that, but in the US, I don't see that happening very soon.

Edit: oh, and also the processor speeds. So, basically I will bet on webapps for mobile after 3-4 years. Until then, at least, installable apps will work better.

Another Edit: perhaps, when something like Google Gears is everywhere, it might change. But offline support - both for code and data - is kind of essential.

HTML 5 includes a storage API, including a SQL database. Apparently the iPhone already has it, and any browser based on WebKit (Nokia, Android?) will likely have it in the not too distant future.

I don't know about processor speed, I can see some intensive 3d special effect games needing native, but for puzzle games, or most 'apps' javascript in a browser is pretty much there.

Lots of stuff benefits from integration with the OS.

It makes sense, webkit is getting so much work for mobile from google and apple and others, why not.