I don't own one but will buy one eventually. Surface Pro is a significant step forward in the world of tablets for a number of reasons. I won't go into all of them here --and I probably haven't recognized them all yet anyway.
1- it's a design that is far more open than iPad. You can move files in and out of it and have full control of the user directory structure. Want to move a bunch of your spreadsheets, recipes, python scripts and chess games into it. No problem. You don't have an Apple-like overlord prohibiting any of that.
2- Need to install XAMPP, Python and other dev tools? No problem?
3- Want to install VMware and boot Ubuntu 12.04 LTS on a VM for a full command-line dev environment and even virtual host a few sites? No problem.
4- and, after all that work, do you want to create a restricted user account for your 5-year-old to be able to play some games and educational apps? No problem at all.
5- How about accounts for guests and friends so that they don't accidentally mess with your stuff? Yup.
6- Need more hard drive space? How about attaching an external USB hard drive and, perhaps keeping all your dev work there for easy transport to your desktop? Yup.
7- Can you use that really cool RC Flight Simulator that comes with a custom USB interface to your JR9505 transmitter? Of course you can.
8- Or, how about that receipt or business card USB scanner?
9- That neat Logithech keyboard you use on all your PC's? Of course.
10- can you run SolidWorks, AutoCAD, Word, Excel, PowerPoint, Dreamweaver, CuteFTP, Komodo, WinForth, Keil, Eclipse, Photoshop, Chrome, Firefox, Safari, Fritz and a whole host of other software you might already be using for fun and work? Sure looks that way.
Yeah. Exactly. Just like an iPad.