The game design is alright, thought this type of game has now been made ad nauseam. The novelty is the mouse control, which works well and doesn't get in the way of gameplay.
The platforming is generally solid, but there is no grace jump and the jump height cannot be modulated. The physics, in general have a few problems. It's possible to scale walls in a pretty inelegant way, and sitting on platforms forces you to move, because the platform's inertia space doesn't affect you. In fact, level 6 and 9 are the only two I skipped because I found contending with the moving platforms tedious.
The theme has been hit pretty well, in the sense that the platforms are not what they seem to be. I completely ignored the typing. Haven't read more than "jump in the void to win" or something and I got the gist.
SFX work for the game.
The music loop of this game has been selected to play in my personal chamber when I'm in hell. Forever. In my chamber, however, it will play correctly, so it will loop when the scenes change. :)
Pretty solid entry, but not my cup of tea.