The people thinking the iPad Pro is just a great big iPad are looking at this wrong. This is a device aimed at business types looking at corporate workflows (and Apple has partnered with both Cisco and IBM), as well as artists who will consider this equipment relatively inexpensive when compared against competing products. Apple isn't really going after Surface, since that's a different market IMO, but instead is going after Wacom Cintiq.
Yes, they will sell plenty of units people not in this group, but those sales will not be anywhere near the sales of the iPad mini and iPad Air 2, which are more mainstream products.
And yes, the iPad Pro has 4 GB RAM. Adobe, and now an iOS developer, have now confirmed this.
BTW, I've been running Split View on my Air 2 for months now, with the iOS 9 beta. While technically it could be implemented on any recent iPad, Apple is restricting it to those iPads with 2 GB or more. Interestingly, the mini 4 is getting Split View too, which is indirect evidence that it too has 2 GB RAM. I skipped the iPad Air update because it was hobbled by 1 GB RAM, and I am very glad I did. Apple specifically leaves out RAM specs to fool unsuspecting consumers, but people on boards such as AnandTech should know better, which is why I was a little bit surprised that techheads at AT immediately jumped on the iPad Air.
As for the new iPhones, IMO the 6s and the 6s+ are going to sell like mad, particularly the rose gold.
And as I've said before, this iPhone 6s/6s+ release is a lot more interesting to me than last year's 6/6+ release in many ways. I specifically skipped that update too because it too was hobbled by 1 GB RAM. I was a little less surprised that so many jumped on the 6/6+ here at AT, because of the bigger screens, but still wondered why so many here didn't wait. Unless they update their phones really frequently, they're going to feel those RAM limitations going forward.
In contrast, I just ordered the rose gold 64 GB 6s yesterday for the wife, because it has Live Photos, 3D Touch, and most importantly because it has 2 GB RAM. 1 GB is lame for a new iDevice in 2015 (and even in 2014). I'm sticking with my 1 GB 5s for the time being though, since I didn't feel like shelling out for two CAD$1000+ iPhones. I'll play with her 6s for a while. If I absolutely must buy it, I will, but otherwise I'll wait for the iPhone 7. I do say most importantly 2 GB RAM, but for my wife though, it's probably Live Photos. She literally cried when she saw that demo. Parents are going to love this feature.
BTW, the new Apple TV also gets 2 GB RAM, so that means all the new iDevices released last week likely have at least 2 GB RAM.
iPhone 6: 2 GB RAM confirmed
iPhone 6+: 2 GB RAM confirmed
iPad Pro: 4 GB RAM confirmed
iPad Air 2: 2 GB RAM confirmed last year
iPad mini 4: 2 GB RAM likely (since it supports Split View)
Apple TV: 2 GB RAM confirmed
1 GB RAM is now legacy.