I doubt Opera will be able to submit to App Store successfully. Maybe for jail broken phones. There’s too much at stake to allow a third-party web browser. If you can include an ad blocker, that’s a lot of developer revenue lost. It’d be nice to have Flash support, but its hard to say how that’ll affect performance and/or stability since Flash was not designed with MacOS, Linux, or other platforms besides Windows.

Norway-based Opera announced Wednesday that it will unveil its new Opera Mini 5 browser for the iPhone at next week's 2010 Mobile World Congress in Barcelona. The developer of the desktop Opera Web browser is touting Opera Mini as faster than Apple's Safari, thanks to its use of compression. Opera said it compresses pages by up to 90 percent before they're sent to the mobile device.

via Opera readies mini browser for iPhone | iPhone Atlas – CNET Reviews.