Well I hope it will install onto the new rmbp's. It's just that the full installers that are currently available (DP1 and PB1) came out before the new rmbp's. Often older installers won't work on newer computers.
I am not suggesting that the final version of Yosemite won't run on the new rmbp's, just that the current developer previews and public beta might not - because they are older than the new rmbp's.
But I am hoping that this is not true. It might not be in this case since, athough the pb1 came out before the 2014 rmbp, the release dates were nevertheless very close.
I'm interested in this too because I also bought a new rmbp. I currently am dual booting mountain lion and yosemite on a 2010 mbp, but I want to get rid of yosemite on that and replace it with lion.
On my new 2014 rmbp, I plan to dual boot mavericks and yosemite. But I ordered online and have not received my rmbp yet, so I don't know if the old yosemite installers will work on the new rmbp's.
If they don't, it might be better to wait till the yosemite golden master is out (which I'm sure will install onto the 2014 rmbp's).