The latest statistics confirm that these decisions did indeed matter:
The results indicate that even taking out the pro se cases, the odds of a court granting a 12(b)(6) motion, at least in part, as compared to denying the motion, were expected to be 1.79 times greater under Iqbal than under Conley (p = 0.002), all other variables held constant.
Second, I used only the cases in my database from 2006 (Jan to Dec) and from 2010 (Jan to May 18), and otherwise limited as described above (no pro se, no magistrate judges). Here, the results indicate that even leaving out the pro se cases, the odds of a court granting a 12(b)(6) motion, at least in part, as compared to denying the motion, were expected to be 1.92 times greater in 2010 than in 2006 (p = 0.013), all other variables held constant.
Run of the mill cases are largely unaffected. The main category of cases where Iqbal and Twombly make a difference are cases where the harmed party must show some kind of behind the scenes activity by defendant insiders which is merely circumstantially established at the outset and then, in past practice, revealed if present during the discovery process. The doors to the federal courthouse are now largely closed to such cases without a whistleblower or some form of domestic espionage. The ruling does not directly apply to state courts.
These motions remain rare, affecting something on the order of 1% of cases on the federal docket, and are granted about three-quarters of the time (up from about two-thirds of the time under prior law).