I want to buy a Mecer LUCID Slate tablet and install unity on the tablet. Thus no keyboard.
Clicking on a text entry field will this bring up a on screen keyboard?
Does uTouch support a on screen keyboard out of the box or do you have to install a package to have this capability?
Currently Unity does not come with an onscreen keyboard of that sort. You can use onboard (open it from dash) to type using the mouse/touchpad, though it won't be a wonderfully smooth experience. Unfortunately there is no "Ubuntu Tablet Edition", so until (if) that happens, you will have to resort to "hacks" or "workarounds" to get such functionality.
Onboard screenshot:
In my opinion florence virtual keyboard seems like the best onscreen keyboard currently available for linux.
Download it from sourceforge.net and compile or install with a deb (older version )
I disagree with the above answer, I think onboard isgood with the right keyboard layouts. If you install ubuntu netbook, you can pin onboard to the side-menu, and then tap on it whenever you need to type.
Trust me, im typing this from my acer tablet.
I think ubuntu is already quite touch-friendly... just search around to make sure somebody else has already got the touchscreen working on your device.