As for your argument itself, it really depends on the use for which you put a tablet to as to whether it's sufficient for the task. As an all-out accounting machine, maybe, maybe not. On the other hand, for photographers, writers and many, many other people the tablet can be the perfect intermediate device that takes up less space (say, at sales meetings) while offering all the 'power' necessary. Even if you do end up needing to carry a bluetooth keyboard, there are times (like at that sales meeting) where it's more convenient to have the keyboard disconnected from the display so you can type without obstructing your clients' view of what you're working with. Simply put, there's a convenience factor that no laptop, not even a convertible-style tablet, can offer. And you just might be surprised at how effective Numbers can be as a spreadsheet app.