But on Tuesday morning, Daring Fireball‘s John Gruber — a blogger with particularly good sources in Cupertino — cut through the fog and offered some clarity.

According to Gruber’s remarkably detailed report:

• The photo here of a MacBook Pro, which surfaced Monday night at Engadget, is the real deal. It shows a black keyboard encased in a single-piece, latch-free aluminum frame.
• There is no $800 or $899 MacBook, as widely rumored. The only Apple notebook computer that will retail for less than $1,000 is the old white 2.1 GHz MacBook, which is getting a price cut from $1,099 to $999.
• The new MacBook Pros come at two price points: $1,999 (2.4 GHz) and $2,499 (2.53 GHz)
• The new MacBooks look like 13-inch versions of the MacBook Pro and come in two configurations: $1,299 (2.0 GHz, 2 GB memory, 160 GB disk) and $1,499 (2.4 GHz, 2 GB memory, 250 GB disk)
• The new machines have no separate trackpad button. The glass trackpad is itself a button. “You just press and it clicks,” writes Gruber. “Sounds odd, but I hear it’s very cool in practice.”
• The new machines are powered by Intel CPUs, but replace the Intel graphics chipsets with a new NVIDIA 9400M GPU (and, in the case of the MacBook Pro, a second NVIDIA 9600M GT). These chipsets can be used to drive an external monitor, including a new $899 24-inch Apple LED display that will also be introduced Tuesday.
• The MacBook Air remains largely unchanged, but with larger hard drives: a 120 GB disk in the low-end model, and a 128 GB solid-state drive in the high-end model.

“Keep your eyes peeled,” warns Gruber, “for jackassery in post-event news coverage, much of which, I predict, will focus on the fact that none of these new machines sell for under $1299. The reality is that these new machines are all steps up, but the rumors that caught the most attention in the past week were the ones regarding $799 and $899 laptops. None of these “$800 new MacBook!” rumors came from anyone with any credibility, but that won’t stop some people from holding it against Apple that they didn’t pan out.”

You can read Gruber’s full report here. He offers no explanation for where he got his information, but given the tenor of his final comments we wouldn’t be surprised if the specs were deliberately leaked to lower expectations that had gotten wildly out of control.

Apple is scheduled to unveil the new MacBook lineup at a special event on its Cupertino campus at 1 p.m. ET (10 a.m. PT).