Just part of the MO of the big investment banks. They pick on a struggling big cap, downgrade it every few days to shake out the weak hands and pick it up cheap. They often try to push it past a technical support level to knock out the technical traders. Then one day (today) someone comes out with a report that is neutral or mildly positive. Soon they'll be upgrading it as cheap, or oversold. After a couple of weeks of runnup, they take the money and move to the next target.

Of course, I have no proof of any of this, I've just seen the movie so many times, and RIMM just looks perfect...