I have just finished a mobile app in HTML5. Although it works fine on iOS and Android 4.x, it caused many problems on Android 2.x. As Android 2.x still has more than 50% of Android market share it is a platform we cannot ignore. I am sticking to native development for now.
I agree with you. I was going to ask this same questoin. From TFA, they stated above. Well, that really sounds like Mark Zuckerberg didn't know what he was talking about at the beginning of this year!
A lot of people are still on Android 2.X as you have stated, and a lot of people are on slow Android devices. I know several people on ZTE Blades running 2.3 which were available over a year ago for less than £100. Sure, not the snappiest of devices, but usable. What is the HTML5 version going to be like for these users?
Blah blah blah, hardware limitations, you can't limit yourself to lowest denominator etc. But Facebook HAS to support all these users. And it's not just users in the western world. There are millions of users in third world countries who pretty much exclusively access Facebook from mobile phones, usually not the latest spec (or even close) or most up to date s/w version (I doubt many would even know how to update it).
I agree that web apps are the way to go. But it is VERY much going to depend on your target audience.
