With regard to the new Calendar app icon--I prefer what the design team originally had [1]. A completely black icon with a number on it does not do much to portray a calendar. Whereas the contrast in the original icon makes it fairly clear.
[1] http://1.bp.blogspot.com/-1TcOt2-N8mI/Uo5L-7skIlI/AAAAAAAAQuA/o4UCQ0T5j8c/s1600/ubuntu-trusty-icons-core-apps.png
With regard to the new Calendar app icon--I prefer what the design team originally had [1]. A completely black icon with a number on it does not do much to portray a calendar. Whereas the contrast in the original icon makes it fairly clear.
[1] http:// 1.bp.blogspot. com/-1TcOt2- N8mI/Uo5L- 7skIlI/ AAAAAAAAQuA/ o4UCQ0T5j8c/ s1600/ubuntu- trusty- icons-core- apps.png