Addressing Vit B 12 deficiency concerns in veganism

Please note that i initially posted this entry on my 43things under the goal of BECOME VEGAN , just for the benefit of fellow vegetarians aspiring to be vegans.
I just decided to repost that entry here for the benefit of the readers here on blogger too .
Here goes the entry:
Firstly, no matter what source, the actual source of the vit B12 are the bacteria.Since farm animals tend to eat foods already rich in Vit B 12 ,primarily because they eat feed contaminated with bacteria that have already produced Vit B12 while in the feed, this vit B12 then gets concentrated in the body parts.Meat is essentially body parts of other animals .Also, it takes an average of 20 years for any type of Vit B 12 deficiency symptoms to manifest since most Vit B12 already present in our body is constantly reabsorbed.So ,technically, if i become vegan now, i might get megaloblastic anemia due to vit B 12 deficiency in 20years.Also, bacteria in our own intestines are perfectly capable of synthesizing Vit B12.Though most of it might not get absorbed,a little of it does get absorbed.This miniscule absorption might on a long consistent basis prevent development of any deficiency per say.Some soy fermented products are claimed to have Vit B12 analogues , which some say might help with preventing deficiency while some others claim might actually hasten development of a deficiency scenario since these analogues compete with the actualy vit B12 which essentially is cyanomcobalamine and thus lead to development of anemia.I am not buying this story of how veganism must cause deficiency syndrome since, I AM VERY VERY SURE THAT NATURE DIDNT INTEND US TO DEPEND ON SOME OTHER ANIMAL'S MILK OR EGGS AT ALL.I did a two years of college in food and nutrition before i started my med school.So, trust me, these entries are being made after being well informed.More info coming up on Vit B12 deficiency soon, as and when I get time and manage to gather up more concrete info on this.Ideally, we should not be needing to grind Vit B12 tablets in our vegan soymilk to make sure we dont end up with deficiencies.I am pretty sure there are plant or bacterial sources.