The DRM systems inherent in movie distribution networks like iTunes, Xbox Live and PlayStation Store are all incompatible with one another. The result is that media bought on iTunes won't work on your consoles, media bought on Xbox Live won't work on your portable media player, and media bought on your PS3 can't be watched on an AppleTV box or Xbox 360.
This deliberate defect in the media products means that when you start buying from one of those stores, you get locked into continuing to use that store and its player on an ongoing basis. Right now, the majority of consumers (of those who have started using digital downloads at all, of course) opt for Apple's store - if that pattern were to continue, Sony and Microsoft's efforts in the console battle would be irrelevant to the wider media business.
The game console makers, however, can take solace in one crucial thing - the weak performance of the AppleTV, a slimline box which is designed to sit underneath your television and provide an interface for purchasing, storing and playing iTunes Store content. Hampered by a high price and restrictive support for video formats, the AppleTV really hasn't taken off as Apple hoped it would. Perhaps it's just ahead of its time - more likely, it's badly designed and positioned, and in need of a rethink. For now, however, this is a major chink in Apple's armour which Sony and Microsoft will hope to exploit.
At the same time, though, Apple is making its own inroads into what might formerly have been considered gaming territory. The Friday before E3, it launched the iPhone 3G into stores around the world - attracting the kind of queues and media frenzy which are normally reserved for a major game console launch. Simultaneously, it launched new operating system software for the entire iPhone and iPod Touch range - which now allow developers to create applications for the devices, and sell them online through the iTunes App Store.
Anyone who doubts the impact of game developers being freed up to work on one of the most desirable pieces of consumer hardware of the past decade would do well to consider two facts. Firstly, the iPhone is a remarkably powerful piece of hardware - estimates we've heard for its ability as a gaming device suggest that it's an easy rival for the PlayStation Portable, prowess which it combines with up to 16Gb of storage, high-speed Internet access (most iPhones are sold with unlimited data contracts, a former stumbling block for mobile network gaming), a unique multi-touch screen interface and an exceptionally precise tilt sensor.
Secondly, take a look at the rough figures from the App Store in its first weekend of operation - compiled by mobile advertising group MediaLets from its monitoring of activity on the store. These figures suggest that games were the most popular applications on the store by a large margin. Almost 30 per cent of App Store products were videogames, and titles like Super Monkey Ball - the top-rated commercial product on the store - pulled in millions of dollars for their creators in the first weekend alone.
Is this the birth of a new mobile gaming platform, then? It's a little early to say whether it'll be an important platform, but the strength of the platform and the performance of games like Monkey Ball and Bejeweled in the early download charts also mean that it would be foolish to write the iPhone off at this stage. It may not be a conventional gaming device in interface terms - but neither were the Wii and the DS, after all. Even if its success in games remains muted, it's another front in what's turning out to be the most interesting corporate battle of the era - not Sony versus Microsoft versus Nintendo, but Apple versus all of them.
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