Just an FYI -- this killed my Virtual Box install the last time i tried it. Uninstalling HAXM fixed it all, but having Virtual Box was more important than the Intel images, so I left it uninstalled.
Feels like they aren't taking window.devicePixelRatio into account so that they end up with a legitimately retina-sized canvas... My canvases were always blurry like this until I took dpr into account.
They make a /huge/ difference, especially if you stay within the tile size.
In fact, using translate3d and CSS animation is pretty much the only way to get smooth animation - if you do it with pure JS (setting left/top styles), things get very herky-jerky.
PhoneGap is getting better with every release, and it isn't too hard to make a nice, functional app. The promise of cross-platform holds only for so long - until either a plugin doesn't exist for the platform or a platform-specific glitch gets in the way, but overall it is a fun and rewarding thing to work with.
I agree -- it is exceptionally difficult to create the look and feel just right in HTML5, CSS3, and JS. I swear that there's an "uncanny valley" for look and feel. To me it is better to bring over some of the "ios"-isms without duplicating the UI (and failing to get 100% right).
One thing I didn't notice, but is important in stoping overscroll is to se the UIWebViewBounce property in Cordova.plist to NO. This ensures you don't have to worry about things like ScrollFix which almost-but-not-quite-solves the same issue. Why Cordova defaults this to YES is beyond me.