If they close below $1 for 30 consecutive days they get a notice of deficiency and have six months to get average closing stock price above $1 again for at least a 30 day period. If not, they get booted from the exchange.
There is a great article on yahoo finance today written by a former hedge fund manager that basically tells you that anything happening upto Febuary is not fundemental driven. It is hedge funds, mutual funds, margin calls, redemptions, liqudations, and tax loss selling. He explains why and how of the machanics. Conclusion until Febuary things will go down beyond any fundemental reason.