Nokia X, X+ and XL will not be updated to X Platform 2.0

Microsoft is going to get a reputation if it keeps doing this – the new Nokia X2 brings a new version of the X platform (2.0) and with it the announcement that the current devices (X, X+ and XL) will not be updated. The same thing happened during the transition from Windows Phone 7.x to 8.0.
Nokia X Platform 2.0 is based on Android API 18 (which corresponds to 4.3 Jelly Bean) and brings a number of changes to the UI. First, there are four tiles per line of the homescreen (up from three) and you can move tiles around and resize them.
The homescreen grew an additional pane – the tiles and Fastlane panes are joined by an app list, just like the one WP has. And as you've probably already noticed, the lonely Back button now has a Home button friend, "for simpler navigation" (why remove it in the first place?). Additional changes include improvements to the camera UI, Fastlane and the virtual keyboard.
It doesn’t sound like Nokia X / X+ / XL owners are missing out on much – yet! – but the X+ and XL only came to the stores last month and are already obsolete.

“Because of the necessary hardware upgrades, the Nokia X software platform 2.0 won’t be available on Nokia X, Nokia X+ or Nokia XL. However, more updates will be coming to further improve the experience of those devices in the coming months,” says Yannis Paniaras, Head of the Mobile Phones UX Design Studio at Microsoft in Beijing.

What hardware requirements isn't specified. The Nokia X2 comes with more RAM than its predecessors (1GB vs. 512MB / 768MB) and better CPU cores (Cortex-A7 vs. A5), but that's about it. And the Home button, of course.