Well.. it's a Tetris clone. Do I have to say more? Maybe I do as there are many variations of Tetris around.
This version tries to follow the Tetris specification by Colin Fahey. According to Colin his specification follows closely to the pre-commercial MS-DOS version's behaviour. (Vladimir Gerasimov's PC version is the first port of the original Electronica 60 version by Alexey Pazhitnov) As the MS-DOS version is available freely from the net, you should be able to compare yourself. (I haven't yet and even if there's some differences, I still might stick to my implementation for some weird reason. :-)
Since I know you aren't interested of reading the specification, I tell shortly here what is missing that you might expect based on your previous experiences.