In fact, right now the option to turn on mining is being removed from the default client - there's no point to mining unless you have a GPU setup. The gold rush has peaked - at this point, only established miners and really determined newcomers will likely set up shop and continue mining.
I'm very new to this entire concept, but for what specific reason has the gold rush "peaked" in your opinion? Aside from the fluctuations of the worth of bitcoins themselves, what variable determines the longevity of mining's profitability? Is the end of this "gold rush" simply a result of new miners driving up the difficulty?