I have debated this one a lot at my current place of employment. Unfortunately, the powers that be are in a "browser only" mode. Personally, I believe in more of a "right tool for the job" way of doing things and in a corporate environment when you have users that are more than casual users, I feel the better user experience is that of a native application. With that said, I believe technologies like ClickOnce (for deployment) and Services (pick your flavor; wcf, rest, etc., to centralize logic) provide the best balance of user experience, performance, security, and manageability. With that said there are times when a browser application is more appropriate. Just depends on the purpose, audience, security requirements, etc. For those that feel native development is dead, just ask yourself if you would rather use Outlook or OWA? Would you rather use Google Docs for word processing or actual MS Word? For a quick check of your email or small update, possible, but if you're writing a large document with complicated formatting (or heaven forbid, your network connection hiccups), would you really want to be working in a browser then?

One that always drives me crazy is how people don't know the difference between a slash and a back slash.