Appcelerator Titanium vs PhoneGap: which produces better native apps?

"better" w/r/t native look & feel, speed, cross-phone issues, development flexibility, etc. [mostly concerned w/ iOS and Android]

PhoneGap isn't made for developing native applications. PhoneGap gives you a better choice for sharing applications with your user. It is the way to transform your application for mobile phones (with a Web Container, like Braden mentioned) and serve it to the Apple App Store and Android Market instead forcing the user to make a bookmark or a shortcut on his homescreen. PhoneGap allows you to use some of the phones features throught APIs to enhance your application.

Titanium is the choice to build native applications without skills in programming language of the mobile phone. For example Titanium takes your Javascript code, analyzes and preprocesses it and then pre-compiles it into a set of symbols that are resolved based on your applications uses of Titanium APIs. So your Javascript is compiled one-to-one into the representative symbols of the native code. UI is built by using the phones native resources.

Conclusion:
Titanium produces better native apps because (of the mapping) they are native. PhoneGap Apps are just Web Apps.