Blu Ray is not necessary. We just need cheaper hard drives so we can install our games. Sell cheap HDD, sell games online, sell retail games with an (or a few) install disk(s), and away we go. You install the game once and forget about it. An external cradle addon that would allow you to insert your own 2.5" HDD of your choice would be excellent, just like the PS3. Microsoft won't allow it though, and will definitely loose out on a money making opportunity this way. Alas, it's not always the smartest people at the top making the decisions, just the ones who have kissed to most butt.
Hell, this could even work in better ways. Imagine a game like Guitar Hero or Rock Band, where you install the game to the hard drive, and when the next one comes out (with guitar hero, that seems every couple of months), the new game stacks on top of the other game. So, you get a new campaign mode, and your QuickPlay mode gains a new song list, without the need to relicense all the tracks for another game. Oh, I wish companies where smarter. Again, stupid people at the top making these decisions.
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