Ubuntu Netbook Edition 10.10 Maverick Meerkat (but this might be used in Ubuntu 10.10 desktop too) will get a new Datetime Indicator which will only display the time and the date will only show up upon clicking the indicator. This is how the Indicator Datetime used to look until today:
But an update today brings a new widget for the Indicator Datetime: a calendar:
The Light Themes were also updated to support this new widget.
Please keep in mind this is the very first release of the calendar widget!