Seeing as how MS is now starting to show signs of the current MacBook/iPhone OSs touch features, I would think a 10.6 Touch announcement would be appropriate right about now before Apple looks like they've been slacking.
Apple has been buying up and developing touch for awhile now and I think they're much further ahead than we think.
One thing to think about is that large touch screens suck, nobody wants to be that close to a desktop or laptop monitor, and they're at the wrong angle. If Apple would do something like an oled touchpad or like a nice
wacom I think they might be onto something....
Touch screen, touch keyboard, no mouse.
They've proven that people can type on glass with no tactile feedback and do it very well. The key to this is the auto spell correction, this, above all, will change the way people use computers. Imagine being able to type on glass at the same speed as a regular keyboard with fewer errors (I can now on my iPhone). This is the one feature I miss when going from my iPhone to a computer, although OSX's spell checker is great now, it doesnt auto correct obviuos mistakes. (like the two in the last sentence)
One things for sure... every Mac running 10.6 will have passed the "Lion Certified Compatibility" program without having to bribe someone.