Should I write my app with Sencha Touch or Native? [closed]

Question

With the recent updates to Sencha Touch, it's looking more and more like a native app for iPhone and even iPad. There are still many differences and the documentation is a little lacking at the moment.

My question is, given that I am already fully capable of creating native app in Objective C, should I switch to Sencha Touch and PhoneGap, or start integrating those tools?

What are the pros and cons?

EDIT:

Thanks for the insightful points. One of my partners wrote up their opinion over the weekend with some ideas that haven't been mentioned here: Web vs Native: How Should You Write Your App?

Answer 1

Pros:

• Easier to port to other platforms.
• You can distribute outside the App Store if the app doesn't require any native APIs.

Cons:

• Scrolling still doesn't feel quite right with any of the web-based touch frameworks.
• Slower (hardware-accelerated CSS animations help, but it's not nearly as flexible as Core Animation).
• Lacks full access to native hardware and OS-integration (PhoneGap provides some, but not everything), such as:
  • Push notifications.
  • Local notifications.
  • Background location updates (including significant location monitoring).
• This is debatable, but in my opinion Cocoa Touch is easier to develop in than JavaScript + Sencha/XUI/etc.