Right now I was in the same boat as the OP but the L2520 might swing it for me:
1) It has LTE for true mobility
2) Slim bezel at 8.9mm
3) The power keyboard is atrociously slim.. yet packs 2 usb ports + a battery extending live by 5hrs or so (hell i thought it was quite thick.. this picture was abit a misleading lol)

4)) has a qualcomm snapdragon 800 cpu [armv7 I think?] MSM8974 (2.2ghz quadcore - 4x krait 400 + adreno 330 gpu)
5) Fast charge - 80% or so in hour!
6) almost a 180 degree viewing angle
7) clearblack display with sunlight readability - I always laughed at my friends when they had cower in the shade in the summer just to read their android phones / iphones screens

8) here maps
9) nokia music
When you compare these to the surface 2:
1) No LTE - apparently LTE Model to be released 2014
2) The bezel is quite thick compared to the L2520
3) Tegra 4 at 1.7ghz
4) charge time rated at 2 to 4 hours.
Apart from the above there is not much difference as the camera or speakers don't really appeal to me as I generally use my headphones and b) I won't be taking pictures with my tablet - that is my L920's job lol. Also both have HDMI out (MS call it HD Video Out), both support miracast, charge time about 10 to 11 hours. The only negative I see about the L2520 is that it only supports upto 32gb with the msd card slot -
Lumia 2520 Spec Sheet.
But there is a solution for that.. this little beauty!

-
Nano Usb 32gb
But I am in two minds right now, I think I will wait for the reviews on WPcentral after which I will look at the other reviews before I make my choice (as I found most reviewers don't know what their talking about - for example mobilegeeks.de reviewer totally missed the office icons in his hands on video, Tom Warren.. well lets just say his hands on video was beyond lazy at best). In the mean time will do some more research on the surface 2.