I haven't heard any announcement about it, and I look for that kind of stuff, but I would think they will add more titles in the future if they added that one. The sooner the better. I have about 15 titles from MGM that I would like to add to my collection, but I won't until they are UV.
I also just noticed some of my above-mentioned Vudu titles with new UltraViolet tags on them. This is indeed curious, and the UltraViolet website still does not list MGM as a partner. This is great news if it mean MGM is finally committing to UV, but it's odd there has been no public announcement.
MGM was mentioned as a disc to digital partner at CES in wait for it...... 2013. Almost 18 months later, they are finally adding some UV titles, but still no disc to digital yet. Also, Hot Tub Time Machine just got a UV label at CinemaNow. Maybe they will add a few each week.