Hmm, "several headers reflect the properties you expect of Photon: optional reliability, sequencing, aggregation of messages, time synchronization and various others", sounds really good. Would be awesome to have these(and more) features implemented.
They say they got reliable udp, but what's the difference between reliable and unreliable udp? I googled a bit and can say now: tcp setting up a connection and getting sure, every packet is sent(reliable and slower). Udp(without connection) is sending regardless if the packet arrived or not(unreliable but faster).
So what's reliable udp then?
edit: I find this also interesting -> link