What did last nights elections mean?

Last night many different elections were held in the United States, but two governor races in New Jersey and Virginia, and a congressional seat in New York were the most important. They were seen as a referendum on Obama's presidency, fittingly taking place a year after he was elected. A few things we learned.
1)The Republican wins in New Jersey and Virginia don't necessarily portend a huge revival in fortune next year, but it certainly can't hurt. It was a good sign to see Independents heavily favouring the Republicans, which was the opposite in last year's election. Most of these voters said it was not a repudiation of Obama, just a sense of lingering unease about how the economy is going. However, it seems to me that it's not a far leap for worries over the economy leading to a huge loss of popularity for Obama and the Democrats.
2)Although the Republicans lost in NY seat 23, it may actually be a good thing. Odds are that a purification campaign in the Republican party will lead to a more conservative party, but not one that can win any elections. Had they picked the moderate candidate they would have won the seat. Better to have the seat and the person only votes for you some of the time, than never being able to count on a vote. Hopefully this takes the winds out of the sails of the more extreme part of the party.
Side points: Gay Marriage was struck down in Maine under a referendum. That makes it 0-31, showing that the majority of Americans don't seem to favour it.
Bloomberg barely won in New York despite spending tens of millions of dollars on his own campaign. It looks like his star has dimmed considerably.