You watch too much TV.
"the Mayans and Nostradamus predicted that the world will come to any end in the year 2012" Nope. You can't quote either's words, as neither mentioned 2012, so I won't bother challenging you to do so. I will just reiterate common sense. No One Can See The Future. Gosh. That's deep.
"It is said that this galactic alignment occurs every 13,000 years" It sure IS said. You just said it. Is it true, however? No, not a word of it. If you look at a circle, can you see the beginning? Gosh, that's deep, too. In 2012, the "alignment" of which you speculate gratuitously, will be OFF by about 6 degrees, slightly GREATER than it was in 2011. That's okay, just keep making stuff up.
Yes, the Mayans were hot about Venus. Hot about Venus. Heh heh. I slay me. Uh, you see, Venus is a very hot planet? Oh, never mind.
ANYWAY... can you provide a citation about the Mayans warning us that when Venus transits the disc of the Sun (doubtful they ever knew about that) that something, anything, bad would happen? You see, I know something. The Mayans only mention 2012 ONCE and that wasn't what they said. In fact (I know, I know, you HATE that word) this is exactly what they DID say about 2012 the ONE AND ONLY TIME they mentioned it:
“"The Thirteenth Bak'tun" will be finished (on) Four Ahaw, the Third of K'ank'in. ? will occur. (It will be) the descent(?) of the Nine Support (?) God(s) to the ?."
When the translator used question marks, he had no clue what the Mayans were talking about, as that particular pillar was damaged.
So, read any good books, lately?
How about http://www.2012hoax.org