Just bought a refurb 4.7. It has a notice that there is an update available and it looks like system.
The Samsung site says 5.1.1 is downloading now.
I can't verify, I turned updates off. There are 2 reasons, I don't like 5.1.1 (have a Nexus 4 with it) and I don't intend to put a SIM card in the tablet. It will be wifi only so I can't tell which version I have. LTE is supposedly the download and 3G is pending. Can't tell w/o SIM.
Since I intend to use tab wifi only, getting MM wouldn't be too bad.