Nothing is uncrackable or un-pirateable (if that's a word), but convenience is a factor in piracy (of anything) and Valve's game appear to be a step beyond casual CD copying or key sharing. This is pretty much what Bioshock sets out to do, only without Steam.
And this may gain them some dollars from those who wouldn't have bought it otherwise, but are so set on playing Bioshock that they pay for a retail copy, (rather than just play some other pirated game for free). Seriously, I doubt this describes a large number of purchases.
But for the sake of completeness, it must also be considered that this policy looses them sales - I took one look at their practises and just moved on, in spite of Bioshock being seemingly right down my alley. If I buy a game, I want to own it. I'm just not interested in paying them that money on those terms.
So, overall, did they win or did they loose? I'd say they lost, because even if they did win out economically (not a given), they still left a number of their customers with a bad taste in their mouth, a bad taste that doesn't necessarily apply to that particular game or publisher alone.
Gaming is supposed to be an enjoyable waste of time. Any needless hassle detracts from that enjoyment. The sense of being cheated detracts from that enjoyment. We are
not a captive audience, we can simply stop playing and do something more productive with our lives. Shift priorities for time and money around.
Antagonising your market is a dubious move - have the efforts of RIAA or MPAA really benefitted the situations of either music listeners or artists? At the end of the day, has it even benefitted the publishers?
Tough copyright practises may well increase the percentage of paid for games, but at the cost of a reduced total market. Was it then good or bad? The question is not that easy, even for the publishers. For the industry as a whole though....