Without the drive and desire to get this Achievement I would have gone out and bought another game. But I didn't. I stuck with Lego Star Wars II and got more out of the game than I would have done in the past. If this continues with the other games that I currently own (and I can already sense it starting) then I'll be buying less games per year and "replaying" the ones that I own a lot more.
This means less of my money will go to the game developers and the publishers. Now I'm only one person (I'm not predicting that I will spell doom for game studios single-handedly) however I'm sure I'm not alone in this. I can imagine that a whole generation of previously hardcore gamers now does the same thing.
With less money going into the industry, only the studios producing the best games will survive, and only the best games will sell in large quantities. As this starts to ripple through the industry the quality of games will start to rise to fight for the reduced money in the market.
Achievements are also starting to show themselves as the differentiator when it comes to multi-platform games. On many a podcast (The Hotspot being one), it is mentioned that, given the choice of multiple platforms on which to play games, the Xbox 360 will be chosen as the Achievements give that extra something to the game and extend the longevity of it. I completely agree, and with extra longevity for these titles comes extra value for money, but only for 360 owners.
The choice of what to buy has never been so great. I've never known so many great games available at one time, and long may it continue. Now all I have to do is find the time to play them all!