Hmmm it seems like it will not be available here in Europe anytime soon, for early-adaptor developers
I cannot even find the Beagleboard-X15 when logged in to my Danish Digikey account and
When trying to order on US Digikey:
http://www.digikey.com/product-detail/en/999-0006389/999-0006389-ND/5324284
I get:
Due to U.S. export controls, we are unable to add this item to your order.
???
Well, it's still a few months from even an announcement for release.
Regards,
It is not for sale yet. Availability is targeted for the November time frame based on SW availability and processors from TI.
Gerald
Assuming it still works similar to the DM814x, you can configure PCIe in PHY-loopback mode, which makes the SERDES send tx data straight back as rx data. Then outbound transactions become inbound transactions and you can access the L3 interconnect via a very scenic route 
How about bare metal programming - is there something like the StarterWare package available for this board/CPU? I could not find something on TI’s webpages, just the old StarterWare package for AM335x…
I am not sure. You would need to ask TI on this one.
Gerald
Unfortunately TI’s StarterWare forum is a mess, you also can ask a stone in the wood - the answer will be similar…
Makes sense, given that StarterWare itself is too.