Apple didn't put arrow keys on the first Mac either. A couple of years later, they did. You know why they waited? Because they wanted to make sure apps that were written to take advantage of the new UI, rather than ported from purely keyboard driven UIs. Why would they put a mouse UI on their first tablet, particularly when Microsoft has demonstrated what a mediocre result that gets you.
I see no reason why, having established touch UI patterns on iOS devices, Apple would have any reason not to start introducing such things on the desktop.
And really, have you been in a pickup lately? They have a lot of car like amenities, like antilock breaks, air conditioners, decent stereos, etc.
Desktop touch functionality wouldn't necessarily be added to the primary display. Apple has filed patents for using touch screens for keyboards and trackpads. Even if it was for the primary display, apple has a patent for a movable display that is oriented horizontally when used as a touch screen.
It's not clear how or whether would add desktop touch features, but they've clearly considered it.
Touching your display is a horrible idea (I wonder how those new windows machines that do this are selling) [1], but the trackpad on the MBP is the thing that finally made me buy one.
[1] Imagine working whole day having to hold your arms up to operate the mouse cursor. My arm hurts just thinking about it.
I see no reason why, having established touch UI patterns on iOS devices, Apple would have any reason not to start introducing such things on the desktop.
And really, have you been in a pickup lately? They have a lot of car like amenities, like antilock breaks, air conditioners, decent stereos, etc.