well does it though ? Data channels seems to use SCTP over DTLS over UDP which would create a sudo "TCP" layer on top of the UDP layer as I understood it :(.
SCTP? That's awesome, I happened to have written an SCTP implementation for my BSc final project and it's a great protocol that makes in-order-delivery optional so it's a great replacement for UDP.
edit: I hadn't heard of WebRTC at all, it looks like a dream come true, not only does it offer SCTP, it offers P2P in the browser, which I believe is going to enable Web 3.0 (yes I'll go there). Sadly they haven't even begun on implementing the Data Channels yet, which is the SCTP part of the spec.
I hope ordered messages will be optional. For gaming and analytics out of order udp is a good enough tradeoff for the better "latency" of not doing acks. The p2p stuff is awesome.