I find the whole, "well so many have been wrong and off about future predictions of much change, so they can't possibly happen" to be a bit of an odd approach to the validity or lack thereof of all such predictions. I guess i don't connect the dots there.
But anyways, yeah i agree worry in relation to such changes is pretty pointless and a total waste of energy. Perhaps because of the lack of worry within this self, and the degree of detachment towards "outer" conditions is part of why i've been recieving info about the changes for so long now?
When many, various more credible sources seem to be saying the same general thing, then i pay close attention especially if i'm getting personal guidance on such issues too. For example, Bruce Moen, Rosiland McKnight's guides, Bob Monroe, Edgar Cayce, many NDE accounts, many indigenous peoples, all seem to be saying the same general thing, that major changes are coming on many levels and that for some, some of these may be upsetting and civilization alterning.
There doesn't have to be anything "fearful" about such changes, but yet humans in general are so scared on average, individually and collectively of "change". Why, because it represents the unknown and calls for less attachment to what's outside of us. We tend to hold and cling to our attachments, as if they were precious gifts, and not the limiting patterns that they really are. We desire and struggle to stay within our comfort levels. Outer change may upset that clinging and may facilitate us realizing that we need to break those attachments or rather replace them with better, more constructive and interally oriented attachments.
In the long run, these changes will be seen to be the best things which could happen to humanity, we will look back with great gratitude and deep appreciation for the temporary "chaos" and challenging catalysts that such changes will have provided for us. Of course, then, we collectively will have grown beyond such emotional fear and materialistic attachments as compared to now.
Btw, as a long time student of the Cayce material, and having read a lot of books based on this material, i have repeatedly noticed a trend and pattern of many authors and critics either misinterpreting or twisting the meaning of certain readings, or taking them too much out of a much larger and very important to consider context. When it comes to the Cayce readings, context, context, context is an extremely important factor and consideration. Of course, Cayce did have blatant predictive errors, but this does not somehow completely invalidate the whole of his work or of his predictions for the future.
My understanding is that Cayce's guides, more than anything, pointed to general trends in relation to the changes, than giving a lot of specific and time based predictions. Most often when dates where actually mentioned, they were mentioned in relation to a long term trend, and telling people to watch the longer term trends, to be observant of same.
For example, the "prediction" his guides most made, in relation to actual time periods, was the prediction of a general global warming trend becoming most noticable in relation the climate of the artic and antartic. He basically said, this would start to become noticeable starting around the year 1958 and becoming ever more apparent, especially towards the year of 1998. 98 and after, would see a real pickup in various changes relating to climate, spiritual awakening, and earth/geological events. Contrary to popular belief, Cayce never gave a definite date for the shifting of the poles, which really should be called the shifting of the Earths crust. There is a reading which mentions the dates of 2000/2001, but if read more carefully and not so narrowly, one would see that Cayce's guides are still outlining more gradual trends. So many authors before this actual date, did the Cayce's work a real disservice when they pointed to this reading and said that it definitively pointed to THE date of a poleshift, no questions asked and no other conditions given, etc.
Considering these first predictions about global warming were given almost some 80 years ago, i would say that this was a definite predictive "hit", unless one still wants to deny that there are major global climate pattern changes going on. Cayce guides though, seem to point to more natural and cyclic Earth and cosmic cycles relating to the cause of this, rather than the more popular and mainstream human pollution cause as many today point too.
While i saw and did not completly agree with Al Gore's movie about global warming, i found something in it very interesting in relation to the Cayce material. Gore mentions one of his professors being really interested in climate and that he became aware or noticing that there was a shifting, a change in the global climate patterns around 58 or 59, though he primarily links to increased carbon emissions. What's interesting is that the 58 period is the exact period that Cayce's guides mentioned many decades before, for being the time frame for starting to notice these climate changes.
What a "coincidence" eh?

It's also coincidental that his guides pointing to 98 being an especially important marking period in this whole changes phenomena. What happened in 98'? Nothing except our Sun aligning to the exact center point in its alignment to the Galactic plane, which only happens once every 6, 500 or so years, and only happens every 13, 000 or so years in relation to the Sun's solstice position in relation to the Galactic plane. We're in the 13,000 cycle peaking phase. Astromically this alignment started in a physically measurable way, in and around the year 1980, reached perfect center point in 1998, and will be in physical alignment till 2016. So we have a 36 year cycle or period of physical/astronomical alignment to this great Center. Cayce couldn't have known about this whole 98' thing, because astronomy/science itself didn't find that out until many years later. Interesting that he just happened to point to this year, more than once, to an especially important marking period, and when the changes would start to BEGIN in earnest.
Sure, but such major and once in only 13,000 or so year Galactic Solar cycles have no import or connection to the destiny of humanity, and to its evolution towards greater and more pure Light.
After all, so many predictions and prophecies, time frames, so many sources, etc. have been so off. But few have had the amount of "coincidences" that this particular above source has had.
As far as "2012" goes, i would say there is a lot of confusion, disinfo, and lack of holistic and clear reasoning in relation to same. The Mayans, like many, were more pointing to general time frames in relation to the changes, and not just pointing to one momentous year. It is and has been a gradual developement, with various marking points in relation to same.
What is interesting about 2012 as compared to other years, is this. It's still within that 36 year Solar Galactic alignment cycle, but also marks the smaller Solar cycle maximum cycle wherein the Sun is scheduled to move into its most intense and active in its 11 year cycle, wherein it has a peak low and high point.
Personally, i see 2008 to 2015 being particularly "change filled" in relation to civilization, humanity, the economy, the geological and climate aspects of Earth, and changes relating to all the above. This in particular may be an extreme and challenging period for many.