Wrong and wrong.
Viedoes showing UI "lag" on swipe gestures are directly attributed to the case housing on the Dev Beta devices impeding gestures from the screen edge. No such problems on Dev alpha units running the latest build of BB10 Developer OS.
As if RIM (one of the more leak proof companies in the mobile handset arena) would hand out testing devices with the Finished UI anyway.
Vertical app drawer was removed and replaced with horizontal scrolling in the app menu in the last iteration of the development release for the BB10 OS.
Don't make the mistake of thinking that Dev alpha handsets have been using BB10 and then assume that the UI you are looking at is therefore BB10 . Dev alphas shipped with a hacked Playbook OS installed.

As for android, AOSP gives F*ck all back to the OSS community or the mainline kernel if it doesn't have a direct monetary benifit to g00gle. sucking in young impressionable devs who think "rooting" a device equals "open" is a tribute to the Apple-esque marketing campaign they have implemented to convince people that it's open.
At least RIm don't pretend they're anything other than what they are.

oh BTW, if you have an N9, you don't have Meego. You have Maemo Harmattan with a bunch of Meego compliant API's thrown in to make you think it's "open".