Hi! I got a Makeblock mBot around two years ago.
Programming mBot using the scratch.mit.edu fork is very easy. The mBot board is basically an arduino uno board so you can program it in the Arduino language too, if you'd like.
One thing I had a lot of trouble with initially was the wireless setup. Makeblock did not do well with making clear instructions for their bluetooth setup- this wasn't a big deal for me as I was able to clear it out quite easily but I could see people getting confused pretty quickly. A couple of other people and I actually wanted to make a Makeblock wiki but that never came to fruition. The github repo is out there somewhere...
Good luck with the programming! Feel free to shoot me a message if you ever need help with your mBot