When the phone memory is near full and the card memory is not, can applications, photos/videos be transferred to the card memory to open up space on the phone?
The easiest way is just to plug into the computer and move the files onto the card using windows explorer. Or you can highlight the photo on your BB and hit options move, but if you have a lot it easier to do it on the computer.
Side note, you should set your cam and video settings to store to the media card.