I did an exhaustive study of tablets for a university I worked for. This was to determine the best device and if they are ready to replace laptops for daily use.

What I found after months of requirements gathering, testing in a lab and real world field testing was:
- tablets are great for information consumption but poor/limited for information creation
- all platforms (iPad, Android, Surface, Blackberry) had strengths and weaknesses
- the cost of fully outfitted tablet equals a solid ultrabook for Total Cost of Ownership

At this point all platforms have a good compliment of software, mobile device management (key for business use) and peripheral devices (attachable keyboards, etc.)

One false promise is the cost being lower. In a business setting, outfitting with dongles for connecting to projectors, monitors, etc., software to provide functionality with enterprise apps, and licensing costs outside of enterprise agreements tips the scale to ultrabooks.

The one advantage was the size/weight of a tablet.

All said an done, I have a great i7 ultrabook and no tablet.

YMMV