Yes, quite smoothly, better than my previous computer (4 YO Dell notebook & Win Vista). It runs the same as ANY mobile computer running Windows 8 Pro with the same hardware: 4 Gb memory, 180 Gb SSD (solid-state drive), 1080p screen resolution (1920 x 1080 and lower), 1 USB3 and 1 HDMI port (you can check the specs online). The SSD makes it feel VERY fast (and quiet). I got the tactile keyboard/cover and it works quite well when needed. The pointing 'stylus' is a good mobile replacement for a mouse.
For daily desktop use, I got a docking station (Toshiba Dynadock) connected via the USB3 port to run a pair of 24" monitors (could run 4 monitors) on extra HDMI, VGA and DVI ports, more USB 3 and USB2 ports and Bluetooth or USB keyboard and mouse. Just pull out the USB cable and the tablet is portable.
When mobile and using RDSS, the battery life is slender - my biggest complaint, about 4 hours depending on usage. You can't get a second battery (you can't open the computer, like the iPad).
These initial Surfaces have no 3 or4 G connectivity (cellular) - only Wifi. That works well for me: 90% of the time it sits on my desk, and while traveling I tether it to my cell phone so Wifi there or at public locations. Other Windows tablets may have built-in cellular and how you add that to existing phone data plans varies by carrier. Other existing or future tablets may offer built-in cellular.
Everything you do with a Windows notebook or Ultrabook, you can do with this tablet. I don't fully enjoy running RDSS in the lower resolution required to actually see things on the tablet screen (full 1920 x 1080 is too small for comfort, though perfect for a large external monitor). So you scale the screen res down to make things larger and you get only the 2 panel layout in RDSS, while I am most used to and much prefer the 3 panel view (i.e. 2 panels of horse info with Analysis panel at the bottom). But it works fine (still gets the winners
).
I don't use the 'Modern UI' much at all, just for browsing using the Win8 version of MS Internet Explorer 10. Mostly, my Surface runs a better version of the Windows 7 Desktop (aka Windows 8).
Definitely check out the other new Windows 8 tablets on offer and compare pricing and specs. I'm sure with newer processors and form factors, battery life should improve, and NEED TO to make these kinds of mobile computers the best they can be for office and mobile handicapping productivity.
Good luck!
Ted