This statement from the following artical caught my attention:

"Another headache for the government was the fact that some devious investors pumped their accounts full of penny stocks and used other schemes designed to take advantage of the TFSA's tax breaks. The government cracked down on that swiftly, closing the loophole."

http://ca.finance.yahoo.com/news/5-reasons-why-tfsas-smart-222737078.html

Is anyone aware of how the government closed these loopholes? I've never heard of any restrictions on what type of stocks you could buy in your TFSA!