Firstly, it is happening. Its the understood sales ratio RIGHT NOW.
Second, sales parity is NOT competition. Please stop confusing the two because they're completely irrelevant. Here's a pretty decent post that should help you tell the difference moving forward. I would suggest reading it BEFORE returning here to comment.
http://m.neogaf.com/showpost.php?p=95488867&postcount=624
We'll all know if you don't. We'll all shame you if you don't. So go...learn.
For your sake.
This isn't coke or beer.... this is technology... competition doesn't start until there is a real threat. Microsoft didn't threaten Sony until last generation. Perhaps you forgot that sony didn't even have a real online service at the start of the PS4 launch or some of the stupid things they did because they thought that they were invincible after the PS2 dominated to the tune of 4:1 over Microsoft. It's rare that you find a Apple who constantly improves their devices and tries and create innovation when they are a market leader by a huge margin and even then some of the best stuff has come with andriod making a serious bid in the tablet and phone markets.