If you are getting a two-second lag on something it is because you are building an application that is blocking on remote assets, not because you are rendering using HTML; there are many native applications on the iPhone (including ones from Apple) that have two-second delays when you click things, and it is because they are pulling information from some API, such as YouTube, to render the content.
As for "feeling", however, there are a ton of little things that are broken: the blue touch highlight sometimes clears and sometimes doesn't (seemingly dependent on the target of the link, not the source), they are doing some silly HTML5 pushState mechanism to mess with the back button incorrectly (specifically, pushing a new state when you go "back" in the UI when that should really pop a state), etc..
The thing that is really freaking me out is that I'm having a hard time figuring out if they are using native scrolling or not (as in, on iOS 5.0, you can just say "this div is scrollable", and not have to re-implement the behavior): the curve seems wrong and glitchy, but they have nailed enough of the actual visual elements that it is no longer obvious to me that it isn't just that they figured out a way to make the native scrolling perform poorly. ;P
As for "feeling", however, there are a ton of little things that are broken: the blue touch highlight sometimes clears and sometimes doesn't (seemingly dependent on the target of the link, not the source), they are doing some silly HTML5 pushState mechanism to mess with the back button incorrectly (specifically, pushing a new state when you go "back" in the UI when that should really pop a state), etc..
The thing that is really freaking me out is that I'm having a hard time figuring out if they are using native scrolling or not (as in, on iOS 5.0, you can just say "this div is scrollable", and not have to re-implement the behavior): the curve seems wrong and glitchy, but they have nailed enough of the actual visual elements that it is no longer obvious to me that it isn't just that they figured out a way to make the native scrolling perform poorly. ;P