I looked into this after repeated references to the game on the 'Darker Days' podcast, and it intrigued me - especially given that it is a limited-run product line like Geist.
This does give you almost all of the tools required for a decent understanding of the game. It provides you with all of the base World of Darkness rules, a full set of pre-generated characters and a module which should give a full nights' play (if not more).
The core themes of 'Promethean' are articulated clearly, and it does present as a very dark game that may not suit every table's tastes (much like Geist). The demonstration kit pulls few punches, and asks for a number of moral choices from the characters as they try to unravel the plot. There are a couple of forced choices, but this is cast in the light of being typical to the setting, and I don't feel that mature players will take exception to them.
I wouldn't recommend this for every group, but I do get the feeling that this is a sleeper success from white Wolf Studios. The types of games you can tell with this do require a depth of emotional maturity, and after reading through this, I feel that chronicles would be best when well-defined in terms of play length and also require a lot of forethought by the Storyteller. That said, it is the sort of play experience which has the potential to be immensely rewarding at the same time.
I'll definitely be looking to trial this with my regular gaming group, and have placed an order for a physical copy of the rulebook - I really want to learn more about this game.
[4 of 5 Stars!]