According TUAW an email from Steve Jobs revealed that the next version of Keynote will include a sort of AirPlay functionality. Specifically, users of Keynote '11 will be able to create a presentation and stream it to the big screen via an Apple TV. This functionality will apparently also work from an iOS device (iPad, iPhone, iPod touch) to an Apple TV.
AirPlay being a major feature in the upcoming iWork '11 may also be the reason for the productivity-suite's apparent delay.
Question: Will the new Apple TV accept keynote presentation via iOS device or a Mac? If it'll, I'll go buy two at an apple store tonight.
It's all coming soon. Stay tuned.