Improved and not easy to measure:

Rendering speed of websites:

-Synology disk station manager web page in Ajax is not 1,5 times faster
-Dutch news site www.deredactie.be renders correctly (before PR 1.2 it gave 2 x some kind of script error: stop running script?

-Skype vid calls: yes yes it kinda works! For some that might be not such a great breakthrough but this N900 device is still foremost a portable phone then computer and adding video is a great thing and no.. not every mobile network provider can or wants to offer an alternative. Over here they charge you per minute for 3G vid calls.

-Ovi maps has now street navigation - no voice guidance, no saving of POI / Landmarks