First of all, even changing it to "preview" isn't really any less mis-leading. This is a concept or mockup. Nothing like a preview, not even a "preview". In saying that, I'd love to see a youtube video for some of your concepts.
Secondly, anything that requires more than one finger to do what I would call a basic task (such as launch a service, go back to home screen etc.) won't work on an iPhone. A phone should be a one handed device (probably the biggest argument for the screen size to remain as it is and why we don't see 5 finger pinch on iPhones). Obvious exception would be pinch to zoom, but that isn't what I would call a basic task, or accessing a service like notifications/dashboards. If you're looking at photo's or in a web browser, your focus is more likely fully on your device.
I like the revamp of the music app, don't really see the same "revamp" in your phone mockup though - which I would like to see.
Mission control, I like the look of the snapshots you have, especially with the app icon in the bottom, but i don't like the access method.
Maps; I personally think that what is shown almost is pointless. Street view would be fantastic instead though! Who knows how long until we can access that quickly (dl speed etc).
Hope that helps feedback wise.