Google demonstrated some of the features they've been working on for Android OS 2.0 Donut while at I/O 2009, and we've got video from the keynote to show you those changes in action. One of the biggest differences to 1.5 Cupcake is "Android Search", which is the catch-all name for the platform's new universal searching that queries contacts, calendars, music and online information.
In addition, Donut brings with it intelligent search, with the Android phone learning common searches and offering them up in future queries. OS 2.0 also allows for simple addition of third-party content to standard searches with just a few line of XML code.
Google also demonstrated an update to their voice-control system, present on OS 1.5 Cupcake, which introduces their new text-to-speech API. A generally available translation app - which currently only shows text translations - was modified with the new API to read out translation results.
Finally, the video shows the new handwriting gestures which can be used to quickly filter out contacts or move through tracklistings in the media player. Let us know what you think in the comments!