There are things that are better done on the desktop. Take Spotify, for example. One of the key to their success is the fact that they keep bandwith costs low by using peer to peer technology.

I've done some research, and found that on average, 80% of the music I listen to on Spotify was coming from peers rather than from Spotify's servers. If I'm anything like an average user, that means that Spotify may be cutting its bandwith costs by something like 80%. That would be impossible to do as a web app, and web-based competitors face huge streaming costs indeed.

Flash has a built in p2p facility

http://www.flashrealtime.com/basics-of-p2p-in-flash/

So does Java :)

But seriously, I don't think Spotify could be the great app it is if it were a flash app. Can you imagine yourself running a tab in your browser with an app like Spotify inside and your fans running full-speed on?

IIRC, Chatroullete was streaming the both audio and video p2p over flash.

The desktop still offers far more support to developers than webapps do. Compare using Qt and Gtk to the mess and hacks required to build web user interfaces. The desktop gives access to hardware: web cams, microphones, printers, scanners, cameras, storage, 3D graphics and proper networking(http is a terrible protocol for a lot of things)

The web as a platform still has trouble keeping up with capabilities of desktop apps from 10 years ago. But due to having pretty much no reasonable competitor in the deployment market and deployment being so essential to a company's success the web will likely continue to be a dominant platform for startups and should eventually catch up to desktop platforms(probably 5 years or so).

>> What kind of enterprise app is better as a desktop app? Other than working if the Internet is down, what are the advantages of desktop over web?

Compute-intensive and graphics-intensive applications

Anywhere where you need local integration that is tighter (or easier) than what you'll get on [preferred web platform].

E.g. for a Windows app: reading files, connecting to Outlook, adding things to the registry, Windows Explorer context menu support, draw stuff on the desktop, plugin for Visual Studio, easier task-tray integration, better global shortcut key support, Win32 API trickery if you need to make controls do what they don't currently do.

Well some apps are only possible if they are on the computer. For my case I created a tool for letting IT agencies keep their software up-to-date on all of their workstations... this doesn't really make sense to be on the Web.

Where security is an issue. For example writing apps for small clinics/patient information.