It is just the avast! News Service and that was the last update news item.
Don't forget that avast 6.0.100 was only released 5 days ago. Plus the iNews also goes out to avast 5.1/5.0 avast versions and I don't believe there is a check function in the iNews to see what version you have installed.
I believe the green I like button will have an option in the avastUI to remove it in an upcoming program update.