Went out the karaoke (ie. noraebang) a few times in Seoul and this was the first one at one of the karaoke places inside COEX Mall. They've got a number of small rooms all with lots of 'decorative' graffiti on the walls and the mirrors of the room.
The most striking and obvious difference between karaoke in chinese establishments (in cities like NY, Toronto, LA, HK etc) and with korean ones is the remote for song selection. It was to much bemusement to find a huge slab bigger than an iPad to use for picking songs. One of the easier ways to look up korean songs is by typing out the song names using the strokes of the korean alphabet - especially if you know the song you want but are a slow korean reader like me (and would take forever to find the name of the artist).