There is still an optical port, doesn't appear that there is any change. A few people have been confused about the adapter necessary and incorrectly stated it isn't available any longer. It is.
http://store.apple.com/us/buy-mac/mac-mini
[url=http://s15.postimg.org/blb44d56v/Screen_Shot_2014_11_01_at_1_40_28_PM.jpg]Image[/url]
You just need a Mini-TOSLINK to TOSLINK adapter, this is a generic adapter which shouldn't cost you more than $2.