If you are the one who is waiting for a new touchscreen iMac then you would be glad to know that Patently Apple revealed some applications made by Apple in Europe that gives a hint that what we can expect in future iMac.
According to the patent, it seems that iMac will run on both iOS and OS X. The switching between the two OS will be interesting according to the direction of screen. When you will use your iMac in upright direction, it will run OS X and while keeping the iMac horizontal it will switch to iOS. Thus you can use it according to your requirement.
Another way is to use touchscreen that is when you want to switch from OS X to iOS then you will need to grab iMAC to 505 left and right as soon in patent figure. These points have advanced touch sensors which sends signals to processor and thus you can easily switch between the two OS.
Apart from this the pantent also revealed about a touch-based MacBook that can be converted into “Tablet Mode”. According to Patent:
The display could also be oriented for touch input. For example, the display 1130 may be rotated and laid flat against the keyboard 1134, with the backside of the display facing down against the keyboard so that the display screen is facing up, in an orientation for touch input.
The new revealed iMac touch seems to be interesting, you can read more about it on Patently Apple.