What is the big difference between this and the stable 10.0.20 ?

I install both on a different server, but cant find the difference  

This update is useful for those who are using 10,1 in some way but there's no major changes, just the same updates as 10.0.20. The difference between the releases is that the 10.1 branch has additional features (e-commerce point store merge, saleable downloads and some other things that will make it to v11 that I cannot recall).