As of right now, only two elections remain unconfirmed. The Democrats picked up the seats they required for a majority in the House Of Representatives and more besides, but the Senate is still a little hard to call settled.
Here's the quick and dirty of this election:
The US government is made up of three branches: the Executive (the President); the Legislative (Congress); and the Judicial (The Supreme Court). These elections decided the Legislative. Congress is made up of two "chambers" - in almost the same way as British politics has the House of Commons and the House of Lords, it's just that over here, both are elected. The Senate consists of 100 Senators - two from each state. In the Senate, each state has equal say and no state has undue power. The House of Representatives consists of 435 members, with varying numbers from each state depending upon its population. In the House, bigger states have a bigger say.
In the House, the Democrats now have 234 seats, Republicans have 201, and one is held by an Independent.
The Senate is closer. The confirmed count at the moment is 49 Republican, 49 Democrat. The two missing seats are Virginia and Montana. Both sets have already been called for the Democrats, and in both, the vote counts show Democrat victories.
The Republican candidates are, the last time I heard, challenging the counts. It would be uncouth, I think, to dwell overmuch on the contrast between the 2006 Republican attitude of "all votes must be counted" and their 2004 and 2000 stance of "be a man and concede you lost for the good of the country".
Other things were decided, too. The Democrats took 6 state Governor's elections.
Referendums were also held. Seven out of eight states voted to make same-sex marriage illegal. Voters in South Dakota, however, overturned the state's abortion ban, and voters in Missouri voted to legalise stem cell research in that state, despite a Federal ban. Initiatives in Colorado and Nevada to make marijuana use legal failed, also defeated was an initiative in South Dakota to make marijuana legal for medical use only. Seven states voted to raise minimum wage. California and Oregon defeated initiatives requiring parental notification for abortions.
Not everything was plain sailing. Wikipedia has a list of confirmed or alleged problems with the running of this election, but of special note is that the FBI is apparently investigating possible instances of "voter intimidation" in Virginia.
Anyway, that was it in a nutshell.
The high point of the day was Jon Stewart and Stephen Colbert joining forces (and their shows, The Daily Show and The Colbert Report) to bring Indecision 2006: Midterm Midtacular on Comedy Central, clips of which you can see at the Comedy Central site.
Priceless, truly priceless.