When the Symantec 11.0.7 mp4 version will release?
There is no officially announced for SEP 11.7 MP4 relased.
Recently 12.1 RU3 has been relase on 6-6-2013.
You can choose this one if you want to update. Because there a lot of feature availble in 12.1 RU3
http://www.symantec.com/connect/blogs/latest-symantec-endpoint-protection-released-sep-121-ru3
11.x will End of Support Life 2014-09-27
What are the Symantec Endpoint Protection (SEP) versions released officially?
http://www.symantec.com/connect/articles/what-are-symantec-endpoint-protection-sep-versions-released-officially
No date has been announced for RU7 MP4.
You can setup email alerts when a new version is released
http://www.symantec.com/business/support/news_bulletins/index.jsp
keep watching on the information forum.