Sitting in on the first third of Ray's HTML 5 intro. He has a "buttload" of code (his word - one wonders about the capacity but I digress) and with his usual efficiency he has posted all his sample code on github here. Great quote from Ray.
"Whenever I hear descriptions of HTML 5 it reminds me of a drug commercial. It's one sentence of benefits followed by 2 minutes of horrible side effects."
As usual Ray teases out some of the most practical and useful tidbits - things that can be used immediately. Make sure and check out the excellent samples at github. Ray also recommends Can I Use - a great site to test your HTML version code.