The whole demo is with the iPhone using EDGE, and it’s fast. The app was submitted a few hours ago and Opera has a countup to when/if Apple lets the new browser into the App Store.
As Chris Forseman said about a month ago on Ars Technica, the reason Opera is so quick on EDGE compared to Mobile Safari is because “It sends URL requests to a proxy server run by Opera, which renders a page into an image that is sent to the phone for display. This method typically offers much faster browsing than downloading an entire page and all its resources and rendering it on most underpowered mobiles, and is especially nice for devices limited to EDGE or slower connections.”