If we limit ourselves to when things got stable in Mid-May, we see that the price has indeed drifted down from ~90 to ~70 then back up to 140, then bounced around between 120 and 140 over a period of weeks[1].

"Relatively stable" is not the same thing as "stable". That's ~40% variance, perhaps more (glanced, didn't do the math.) While not as bad as 260-130, it still ain't pretty.

[1] http://bitcoincharts.com/charts/mtgoxUSD#rg180ztgCzm1g10zm2g...