I am convinced that Apple will release a retina iMac in late 2013, and chances are, it will be a "Pro" model to replace the Mac Pro.

After listening to a recent episode of Hypercritical, I started thinking heavily about Apple's retina roadmap. A few things are known for sure.

  1. Costs for retina Mac displays are high and yields are low.
  2. Because of the above, Apple sells the retina MacBook Pro as a bleeding-edge notebook for high-end professionals.
  3. Apple isn't afraid to set aside a retina model of an existing product line.
  4. Apple hasn't truly updated the Mac Pro since 2010.
  5. Tim Cook has promised something new for professionals in late 2013.
  6. It's in Apple's best interests to upgrade the entire lineup to retina as soon as possible.

The rumor mill is convinced that a retina 13" Macbook Pro is coming soon. That would be the logical next step after the 15" Macbook Pro, but the more interesting question is why Apple chose the Macbook Pro as the first for retina.

Simply put, it's a balance between screen size and available power. Apple's current idea of a professional-sized display is 27", as seen in the high-end iMac and the Thunderbolt Display.

LCDs are manufactured in giant sheets and cut to size. So, for every 27" screen they cut, they could instead produce nearly two more 15" displays. (Thanks to the commenters for checking my questionable screen math.)

Why Not the Air?

"Ah," you say, "but if screen size is key, then why not go ahead with 11" and 13" Airs? That's a lot of screens per sheet." Fair question, but there are a few reasons why I think the Macbook Air will be the last of the line to receive retina screens:

  1. The Air currently has no space for a dedicated graphics processor. The current Retina Macbook, despite its beefy hardware, has a hard time pushing all those pixels.
  2. The Air is the entry-level Apple laptop. Retina displays are cost prohibitive, and Apple needs to further distinguish their "Pro" line.
  3. Retina screens need more power and cooling. Apple managed to make the retina MacBook thinner and lighter by making it more like an Air. The Air doesn't have the room to spare.
  4. The Air already has a better screen resolution than most Macbook Pros.

That's not to say the Air will never see a Retina update. It surely will, but don't hold your breath while you wait.

Why Not a Retina Cinema Display with a New Mac Pro?

There's a very simple answer for the first part: Thunderbolt can't handle retina. The current implementation of Thunderbolt can transmit at 20Gbps, at best. A 27", 5120x2880 display with 24-bit color would require at least 21 Gbps. There is a rumored Thunderbolt upgrade coming in late 2013 or early 2013 that would enable that, which has led many to speculate on a new Mac Pro around that time.

But why not a new Mac Pro? With Tim Cook at the helm, it comes down to the supply chain. What do the Mac Mini, Macbook Air, Macbook Pro, and iMac all have in common?

They're laptops. They use mobile chipsets, mobile video cards, mobile RAM. They can buy huge batches of the same parts, and use them to reach four distinct segments of the market. The Mac Pro sits as the lone-wolf "true desktop" in Apple's lineup.

Why would Tim Cook want to maintain a completely separate supply chain for just one low-volume product? Sorry Mac Pro fans, but it just doesn't fit into the lineup anymore.

Why the iMac?

With the Mac Pro gone, the iMac is the next best thing. That will infuriate professionals, but as we saw with Final Cut Pro X, Apple is willing to anger the pro market to reach a larger audience.

Despite the iMac being a glorified laptop, it has a couple of key advantages that make it a better retina candidate than the Air. First, battery consumption isn't a concern. Second, there's more room for a better graphics card to push all those pixels.

But Why an iMac Pro?

Because it won't be cheap. I wouldn't be surprised if a 27" retina iMac pushed near the $3,000 price point currently owned by the Mac Pro.

But what the iMac Pro will be is exciting. No one gets excited over the Mac Pro. Either you need it or you don't, and if you need it, you need the fastest you can afford. It's a beautifully designed hammer.

An iMac Pro would tempt people who wouldn't think twice about a Mac Pro. Even if they don't buy one, maybe they feel compelled to "settle" for the non-retina model.

Conclusion

It all comes back to the four-square product matrix Steve Jobs laid out when he returned to Apple. Consumer portable (Macbook Air), professional portable (Macbook Pro), consumer desktop (iMac), professional desktop (iMac Pro).

I don't have inside connections or a crystal ball, but the advantages of an iMac Pro are clear: A simpler supply chain and a renewed interest in the iMac lineup.

I'm not sure if Apple is heading in this direction, but it looks like they could be, and they'd be crazy not to. Power users will be angry at the death of the Mac Pro, but a 5120x2880 27" iMac might ease the pain.