I am pretty sure Valve/steam is learing as they go and making it harder to pirate.
/steps on the pulpit
I for one support people paying for their games. End result is that the creative people who make good games are rewarded and ultimately the consumer is rewareded with better games. Otherwise those creative people go do other things so that they can put food on the table. One of the few cases where I support the company over the (illegal) consumer.
/steps off the pulpit
Episode 1 is giving me that urge to load up half-life 2 and give that plus EP1 a shot. Other contenders for next game are R:TW, Sims2, Halo, Oblivion. Sadly the list of games I want to play is always growing due to a lack of gaming time. Better than not having any good games to play