I can't believe people wrote almost 80 pages trying to figure out whether MA is a con or not. To me the answer is pretty clear. Let me summarize for those who don't want to dig through (and rightly so) all that MA bs :
1. Dow to hit 32-40K by 2015 - wrong
2. Gold to hit 5K by 2015 - wrong
3. Peak in government (which in his own interpretation means high in bonds and further collapse) by 2015.75 - wrong
4. USD to further decline in 2011 - wrong
5. Absolute high in real estate in 2007 - wrong
and the list goes on...
So, not just 1%-10% wrong but wrong big time. Also, he missed the recent commodity collapse and particularly oil.

Ok, everybody makes mistakes, no big deal, right? However, MA never ever admits he is wrong. Has anyone witnessed he ever admitted he was wrong? Yet he always bashes politicians for not admitting their mistakes. Furthermore, he keeps repeating that people with no trading experience are capable of nothing, can't run anything etc. Yet he, with no experience in politics, law, and many other things including economics, always comment on those and many other issues in which he clearly has no knowledge whatsoever. In fact, he did not even have a college degree.
Now, how does he manage to get away with all that? Just a few of many more tricks below:
1. Not being specific by obfuscating everything and making predictions very vague (ex: "everything will go nuts from there" or "when people lose confidence")
2. Giving a wide range of possibilities (ex. "the resistance levels on the euro 1.16, 1.20, 1.40 etc)
3. Using words like "can", "may", "possible", "there is a chance", etc. (you can't be wrong making such predictions, can you?)
4. Shifting dates (ex. with the Dow first it was 2015, then it became 2017 and now he is shifting the date to 2020-2021)
5. Using his 3.14 model
6. "It's not me, it's the computer" (if a prediction is right, he claims he is right, if wrong - he never admits it but it is assumed that it's the computer's miss)
7. Throwing lots of predictions (incl contradictory ones). One of them will always be right by definition. Then he goes like "I warned", "I told you so", but never mentions failed ones so it gives you a false impression that MA is a genius and is always right
8. Constantly bullshitting you by bringing up something on history and physics so that his predictions could look more credible and to create an aura of a guru
 
What is also interesting is that he goes way out of his way to reinforce that idea of exclusivity of his analysis by keeping babbling about:
1. Unique computer model
2. Unique historic data that cost hundreds of millions
3. Unique approach etc
that you may wonder why? Looks like somebody is trying to sell you something, no? The reality is that nobody saw his computer (so it may very well be yet another bs), his data or anything. He claims that everybody  sells you their newsletters, subscriptions etc. He is the only one who does not because he is filthy rich (in his own words "the markets have been like an ATM machine for me") and has a higher calling in life - to bring knowledge to the masses and all that. Yet he sells some bs dvds, reports, coins, etc, at exorbitant prices and charges thousands for conferences.
Something just does not add up here to say the least.