I was going to try and answer the questions I could as best as I could. But then I looked back at my Mothers posts (Sharon) and saw that she already has.
But I will highlight them again.
And will there be an option after 2014 to continue to not use barrels?
Answer:
Mid-2013 and that will be optional until mid-2014. Many clubs want to add barrels and they will be allowed to do so.... while other clubs won't have to if they don't want to for another year.
Detailed answer: Not Mandatory until 2014.
So barrels will become a required obstacle in mid-2014?
Yes.
And now for the questions that weren't answered I will do my best.
If we are going to see barrels at champs, I as well as many exhibitors that attend my trials and will attend champs next year would really like to see barrels before mid 2013. We need to practice them at trials.
So can the timeline please change to January 2013?
I can't really say anything definitive since I don't sign the paychecks

But my gut feeling is that if a club is good with using barrels, and even better wants to see them, then it would not be hard to get courses with barrels.
My interpretation of the above statement about when they will start making star appearances is that in 2013 your judge may get courses that have barrels on them, but if your club has no barrels, or no desire to add them then those courses would not be chosen. Where as in 2014 the clubs will be required to have them. And the courses being picked will no longer be brought into the picture. Again this is just my interpretation based on a educated opinion.
Can a club put a barrel out in the warm up area- even if they are not being used at the trial? That way people can see what they are.
I see no reason you can't. Make it clear it's just there for demonstration and not going to be used in the trial just to contain any possible issues

What is the purpose of the barrels? Are they replacing another piece of equipment? I'm trying to visualize the purpose and how they would be used on the agility course, say Regular for instance or are they just part of the games classes.
Do the dogs just run up to them, then around them and on to the next piece of equipment on course? Looks like I'll have to teach Savannah another skill for this piece of equipment.
They are being brought in as a entirely new piece. If they would be replacing anything consistently, it would be U-shaped tunnels.
As for how they are performed. For now they are being used as Bi-Directional obstacles. So for the U-shaped tunnel example it would be performed in the exact same way as a tunnel, pick a side and go around it. If your dog is quick and efficient on his turns he does it faster and gets a better time. Inefficient and the inverse is true.
I personally like the idea of the barrels as they will add a very large number of options to a course once they are being used to their full potential. And for someone who has been doing agility their entire life, some new options are a very welcomed thing

I would gladly give multiple examples of how a barrel is used, but in my experience trying to explain something simplistically through a computer with my words...well it tends to get cluttered
Next time I am out working with barrels I will shoot some video and get it uploaded for you guys to see some options.