This could very well be the cause of the delay of the Retina MacBook Pros as I have pointed out a few weeks ago:
So there are some things that do not make any sense. Let me lay them out for you:
First of all, what would be the real reason for Apple to delay the release of the new Pro machines? This is the really interesting question here. The aforementioned reasons can not be the whole story behind this.
I'd like to point out a few additional reasons why Apple delayed the launch. All of the listed features [which were mentioned in the news post] could have been released at WWDC.
1. IGZO displays. These things just faded a little bit in the background rumor-wise - at first glance.
But wait a second: A reason why the release has been delayed is the low supply of display panels (see news post).
Apple has problems with getting the LCD technology which they had time to produce for more than a year now? That simply does not make any sense at all.
What makes considerably more sense is, that Apple will switch to IGZO Displays because they offer superiour quality and incredibly lower power consumption -> providing more battery life and allowing the 13" MBP to become thinner.
The 15.4" displays with IGZO technology are in production by Sharp for just a few weeks. I'd call this a bottleneck right now. It fits very well in the prediction by KGI.
2. Thunderbolt 2: Apple just gave a sneak peak of what they have been working on in terms of Mac Pro. One feature was very apparent: Support for 4K displays.
As of right now, the Retina MacBook Pros only support Thunderbolt 1, which does not offer the throughput which 4K displays require.
Thunderbolt 2 on the other hand will provide just that.
So, let me ask you: What would be the point in introducing a new Mac Pro with support for 4K displays and later on introducing a MacBook Pro without support for this technology? Apple would be foolish not to include this technology [Thunderbolt 2] in the new Retina MacBook Pro!
This is because Apple will very likely introduce a 4K cinema display as soon as the new MacPro goes on sale.
To provide such a display at a sufficient price Apple needs the effect of Economies of Scale.
Therefore they need as many potential customers for such a display as they can. The new Retina MacBook Pro has to incorporate 4K support with Thunderbolt 2 to do so! The downside: Thunderbolt 2 will not be ready until fall but Apple has to incorporate this tech due to the reasons I just mentioned. Before you ask: Yes, the new Retina MacBook Pro GPUs will offer support for 4K displays; in fact, if you bump up the current rMBP to the highest resulution (1920x1080) it already renders nearly 4K resolution (1920x1080 times two in every direction). So GPU-wise it is already possible, but the connector is not ready yet -> delay.
These are my two top reasons for the delay. Hit the like button if you agree. Flame away if you don't.