hey there Khalid,
You and I have been troubled by the same sort of speculations, and believe me, I have spent days reading articles and facts about astronomy, the Mayans, Islam and so on. The conclusion that I have come to can be summarised in these few points:
1. Since nobody knows the exact date of judgement day as Allah does no reveal it to us in any way we cannot specify the date and time. However, this does not necessarily mean that we are not able to scientifically predict when certain signs for the day of judgement shall take place. Other than the ending of the Mayan calendar, I have read that on the 21st of Dec. 2012 (the day the Mayan calendar ends) the sun will experience a polar shift due to its 11 year solar cycle which is completely natural since it has always been happening since the beginning of time. The outcome of such a phenomenon is what has been keeping me on edge. Due to the planets' positions on that day, and to the galactic alignment that shall also take place on that day, and to the Earth's weak magnetic field, the Earth shall be affected in a terrible way and might also witness a polar shift meaning the north will become south and the south will become north. Do you know what that means? The sun will seem to rise from the West. Not only that, it will cause a huge disruption to the Earth so that there will be floods, earthquakes, eruptions, you name it. Disasters will take over. Because of the eruption of these volcanoes, smoke will prevail and the sun and the other planets shall be blocked from us till God knows when. The thing that really got to me is this: the sun's rising from the West is one of the big signs isn't it? And right before that -because of the polar shift that will be going on- there will be no sun for a few nights! Another big sign is the smoke! And yet another big sign is the long nights! Look, Allah did not tell us when the day of judgement shall arrive, but Allah provided us with the signs, and if you read Quran you will find that Allah orders us to
think in so many verses there. We need to think and use our brains. Of course, no one knows the exact date but that does not mean we won't know about the coming of the signs. We have great science and technology and that's where are they are pointing at. Of the other many things that we do not know is how long we will live. Does anyone know when they will die? I don't think so. But if someone has cancer or AIDS, then a doctor might be able to make a prediction about how long that person is going to live for, and a lot of the time, they are right about it. So, I think this is the case we're dealing with here.
2. Nobody knows the exact chronological order of the major signs we are about to witness, so whoever tells you that the dajjal needs to appear first is wrong. Nobody knows and the sign of the sun might be one of the first few. I would also like to add that the 21st of December is a Friday. Another weird coincidence.
3. We (Muslims) are not the only ones awaiting judgement day. Christians believe that the Antichrist (dajjal) is going to appear on the 21st of May 2011. They have been waiting for this day since 1988. You can check if you want, there's a book called 'To God be the Glory' by 'Harold Camping'. You can even find a version of this book on the internet in the form of a pdf file. Is this another coincidence?
4. The Mayans predictions are not based on anything false such as magic or horoscopes or the like of these absurd ways. They were a very intelligent people who used to be great scientists in maths, astronomy and I don't know what else. The bottom line is, they were not just making a wild guess when they set the date. They had reasons to believe that the Earth would be ruined on that specific day because of the position of the planets and equinoxes. By the way, I have read that they used to live in Atlantis, and we all know that Atlantis has drowned. We do not know much about them and that made me wonder, who was their prophet and why were they drowned? Some of them did not drown and that's how they moved to Mexico and Egypt. Perhaps their drowning was a punishment of Allah's like many other peoples who denied the prophets and the ones that lived might have been the good ones? Remember that Allah did not tell us about all the prophets sent on Earth.
I think this is most of what I have come to regarding this issue. I hope my answers have been helpful. But let me add one thing: if the sun really rises from the West that day, know that all doors to repentance shall be closed and tawbeh will be too late. We had better get ready for what is coming to us. 3 years are the longest we have for nobody knows how long we shall live
I also read that in the same year when the big signs shall arrive, the middle of Ramadan will be a Friday. Look at 2012 by yourself. You will see that it is a Friday. Another coincidence? And look at how strange the numbers are, if you add every two digits together the sum is 3. The same is with the Hijri year, it will be 1433 Hijri, that also strikes me as too strange to be a coincidence.
That's my comment about the subject. I shall be pleased to hear anyone else's comments about my findings.
Happy Ramadan!
brothers and sister 
