Do a search here on page transitions, you'll find lots of discussions about it, as well as several ways to address that. It's a (well) known issue with 1.1 transitions, and has been reported, at least in one case, to have an app rejected from Apple. watusiware created a script that can revert them to the 1.0.1 types more or less.
As far as images loading slowly, that seems really strange, particularly if they're local. Are you sure they're not really large in size? Also, setting the dimensions in the <img> tag can make them appear to load more quickly (less page jumping).
I have been using vclick for buttons inside of scrollers, and vmousedown for non-scrolling buttons. So, inside of scrollers, it fires when the user lifts their finger. Outside of scrollers, it fires as soon as the user touches. This is great for an application menu.
I use vclick inside of scrollers because of the logical impossibility of using vmousedown, since there's no way of knowing in advance (without some quantum-entanglement technology... ;) ) whether the user is intending to tap or scroll when they first touch the screen.
I don't use <a> tags or buttons, but simply attach a vclick or vmousedown handler to a <div>. Of course, then, you have to handle any "button down" and "selected" states yourself (and clear them upon returning to the page from a link). By not using <a> or buttons, I don't have to worry about either the browser or JQM applying effects that I don't want them to apply.
It's really quite simple to do. I'm not sure why so many of the solutions presented for this are so complex. I haven't had any issues with "phantom clicks" from vclick, but it might just be lucky placement of UI elements.
If you combine this with "none" transitions and write your own lists from simple HTML (instead of using the bloated listview), you can produce native apps with HTML UIs using jQuery Mobile that feel native and respond instantly.
It is true that sometimes JQuery in combination with PHONEGAP seems to be slow.
It is not the fault of JQuery or Phonegap but well the fault of the developers. Why?
1) Phonegap is not slow at all, it is the WebView (natively implemented by Apple, Google...) bused by Phonegap to display the User Interface. From iOS6 it is true that everything becomes extremelly slow.
2) JQuery is an extremelly good tool but sometimes too good. I mean people are developing their User Interface and mobile app in a Desktop Browser and discover when starting tests on the mobiles devices that everything is becoming slow. Do not forget to optimize your code !!! (Every ms counts!) I see too often coding like:
Please keep references to the jquery dom elements ! I have also posted a class on the Forum UtilDom extremelly useful to access dom elements who nevers changes using a kind of caching system. This class ensures sometimes a performing 3000 faster than JQuery out of the box.
In // now to avoid such slow transitions on devices, we are running most of our pageshow and pagebeforeshow content in a <> Thread and we are mapping our buttons with touchStart events
The combination of all those tips are ensuring a performant app even running on ios6.
PS: JQUERY 1.0 is much more efficient on iOS6 than version >= 1.1
Here the class code we are using to run the content of pageshow and pagebeforeshow in a <> Thread:
UtilForker = new Object();
//For logging purposes
UtilForker.TAG = "UtilForker.JS: ";
* fork start a new Thread to execute the given method
* @param methodToExecuteInForkThread: the method to start in a forked thread