Where's the one-thumb typing on WP8 ?

I've been reading some rumors before Windows Phone 8 launched and I stumbled upon this:


And then I thought It was a great idea, and I was looking very forward for that feature.

A few months later , Window Phone 8 launched, then nothing. No sign of any one-thumb typing keyboard.

I was wee bit disappointed. It looked like it was a great feature and a mimic for Windows Phone.

Microsoft REALLY have to put this feature in Windows Phone 8.5. As well as charms bar for Windows Phone.