In general I'll be using it for kindle reading, web browsing, light gaming, social media, email, etc. Same simple stuff I use my iPad 2 for.
Specifically I'm going on vacation soon, so I'll be using it for movies, reading, games on the flight. iPad2 could do that, but with the 4x3 display and 32 Gigs I wouldn't have much to choose from and it would be small pictures.
Also, during my vacation I'll be using it daily to move pictures and videos that I take on my DSLR and phone during my touring days to the Surface. Then at the end of the vacation when I get home I'll offload them all onto my PC for editing together. I couldn't do that with the iPad at all since there's no file management on the iPad to speak of. I'll have 64G built on board and a 64G Micro-SD card.
I can't believe the bargain that the Surface RT represents - they can be had new for under $250 with 64G storage!