According to Mackubin Owens, the "failure of intelligence" leading to 9/11 was a result of "congressional reforms that forced [the CIA] to shift to from the use of human assets to reliance on technology." Of course, Peter Beinart was blaming a bureaucratic CIA back in February (although he complained that Congress wasn't overseeing it enough). And former agent Reuel Marc Gerecht was explaining the fecklessness of the CIA's efforts against Osama bin Laden last summer, before the WTC attack even happened. Another former agent, Robert Baer, has written a book more or less corroborating the others' views.
Personally, I've always taken it for granted that a huge, widely-known government bureaucracy can't possibly be an effective intelligence agency, and I've therefore been assuming all along that the CIA has been a dead letter (and known as such by those who matter) ever since it became every paranoid's favorite obsession back in the 70's. In recent years, the NSA, which had taken over from the emasculated CIA the role of main source of intelligence for the US government, has also become noticeably huge, famous, and popular among paranoids--right around the time that the proliferation of effective encryption technology has rendered its signals intelligence-based approach nearly useless against many of its most important targets. Even the shadowy NRO, the agency responsible for satellite reconnaissance, has become relatively familiar of late--along with its commercial competitors, who sell the same capabilities at surprisingly affordable rates--prompting those with secrets to take care to hide them from the skies.
So who's doing the real spying these days? Well, I've spotted scattered mentions of something called the Special Collection Service, or SCS, a small organization specializing in more "direct" intelligence collection methods than the NSA's and NRO's (to say nothing of the CIA's, which, according to the aforementioned critics, amount to sitting in plush offices in embassy compounds). There seems to be little publicly available information about them, though.
Sounds promising to me.