On another note, upon submitting a test blockchain address, Bitvisit is able to know the balance there.
This actually got me horrified.
I wouldn't be horrified.
There is not a whole lot anyone can do with just a bitcoin address.
It is well publicized that whoever owns this address is worth at least $10 million :
1933phfhK3ZgFQNLGSDXvqCn32k2buXY8a
But no one knows who or where that is exactly.
Put that in blockchain.info and take a look.
Source:
http://www.businessweek.com/articles/2013-04-10/meet-the-bitcoin-millionaires