You expect the resource usage to fall when apps go native? I wouldn't. Sure, any given executable can be more optimized, but the scope of an application can be an order of magnitude greater. Each developer doing their own asset management to boot.

Right now the HTML renderer and JS interpreter are essentially running all the time. Each application a sort of advanced web page. Running multiple applets isn't going to be such a big deal.

There are plenty of iPhone apps out right now that will suck down every byte of available memory on the device. When you're running a web browser, a game, a paint program and an audio sampling/mixing application, things are going to get tight, I don't care what platform you're on.

The Pre isn't magic and its components are all filled with the same blue smoke as everyone else's.

I'd classify the battery usage performance (duration) of the iPhone as above average and that of the iPod Touch as far above average. Taking into account of course what you're actually doing while using up that charge.