Don't forget to order your supplies for this year's International BookCrossing Day (April 21)! The last day to order them is March 25, because we'll need time to get them to you before the big day arrives. And this year's labels were designed by Azuki and they're great. So don't miss out, get your orders in while you can!
That is totally up to you. I more or less regularly take a look at my local region, as I know that my city often gets created in the wrong region, and then when I have free time I drop by this forum and see what I can help with. I leave more difficult and iffy stuff to those who are more experienced, and mostly handle simple merging of duplicate zones.
You are not obligated to do anything, you are just given the tools to help, and you can jump in whenever suits you best.