Being in California my opinion is that it's a wonderful idea, but the ballot initiative is really flawed (as is often the case with voter written legislation). The way it is written it will have a ton of unintended consequences in part because of the exemptions and frankly many food processors don't really know whether their supplies are GMO or not. (Perhaps that's part of the purpose).
As far as GMOs goes, I would rather not eat foods that have DNA imported from a completely different organism, but genetic manipulation is what breeding programs are all about, so we have, in essence, been eating GMOs since the first farmers started saving seeds from plants that exhibited some prefered characteristic.
I really hate the Monsanto GMOs that have created herbicide resistant plants so farmers can spray the heck out of fields, but GMOs that have enhances nutrient qualities, like golden rice, seem ultimately beneficial for populations that cannot get enough vitamin A (I think it is A... but don't quote me) through their regular diet.
I think the GMO question is really complicated, and to universally ban them as some countries have done, is probably short sighted. But I do agree that consumers ought to have enough information to make informed choices, just as we do when we are comparing a can of beans that has added sugar or salt vs. one w/o the sugar & salt. I'm just do not think that the proposed ballot measure is the right mechanism.
2.5 years, 45 pounds later... 128ish pounds