Last Updated Apr 13, 2010 1:13 PM EDT
As the video shows, Opera provides some impressive abilities: speed, tabbed browsing, quick panning over an entire page. Page loads are much, much faster than Safari. That could technically be the reason why Apple approved it and not Google Voice:
This is why Apple's demand to completely control the ecosystem around the iPhone OS is so dangerous to companies that want to create apps for the platform, and why Apple's approach will ultimately fail. The problem is not the desire to lock in developers and keep out competition, so much as the arbitrary way in which Apple wields that power. Smart business requires that you calculate and manage risk. But software companies can't be sure how Apple will apply judgment and whether their investments will come to fruition or naught.
I suspect that is why Apple approved the Opera browser. There wasn't an obvious issue with look and feel, the company poses no threat to Apple, and it gives hope to developers, which is vital. The iPhone OS business stands on a stack of cards: Business cards of all the app developers who want to make money.
Apple is unlikely to disclose this data, but I suspect the distribution of income for paid apps is incredibly lopsided, with a relative handful doing very well and the vast majority making modest amounts, if anything. Apple runs the risk that developers may end up disillusioned from seeing their work in a dumping ground of 150,000 other app choices a consumer could make. Concerns over draconian restrictions in the developer agreement only aggravate that possibility. Every once in a while, Apple had to do something to seem reasonable and give developers hope. I think that's exactly what the Opera approval was all about.
Opera Image: Flickr user Tom (Todas con licencia CC, AtribuciÃ³n), CC 2.0.